722.4 no reverse engagement

[Jens]

On my 1991 300SEL (W140, 722.4 transmission) the reverse gear first
went very slow (10-20 seconds) to engage. When engaged, it worked
without slipping. Now (a week later) it does not engage at all.

From other postings I can read, that the problem probably related to
the engagement mechanism for the B3 clutch, and that it may be fixed
without removing and disassembling the transmission.

I could however not find further information on what exactly to do and
where to locate the relevant parts.

Can anyone help?

If I have to disassemle the transmission, is there any hints of what
to look for, and eventually a recommandation of what else to do, when
it is taken apart anyway?

[Tiger]

http://www.transtec.com/tech_insert/94642.pdf

[Jens]

Post by Tiger
http://www.transtec.com/tech_insert/94642.pdf

Thanks Tiger, you're always there.

I always try to understand the problem before doing something, and the
link supplements the ATSG manual (which I do have) quite well).

From this I understand, that the B3 piston clearance should be
checked. But it does not provide information of how to adjust it. I
guess it is adjusted by selecting the thickness of steel and friction
plates.

From an old posting I read:

"Check the reverse (B3) band adjusting stud- it's on the lower front
right
corner of the case, behind the kickdown solenoid. if it is loose and
has
backed out, screw it back in and tighten the locknut, leaving three
threads
showing above the locknut.
Next in order of probability is a broken B3 apply piston, on the
opposite
side of the case. Pretty easy to do in the car."

So, I was hoping something could be done without taken transmission
apart. But I don't see how that information fits with my transmission
(which in fact is 722.368 - not 722.4 as I first thought). Do you (or
anyone else) happen to know about this?

Furhermore, the ATSG guide for reverse problems are:
1.Check lining plates and lip sealing rings on piston LB3.
2.Check one-way clutch.

This suggest that problem could also be en "F" clutch ("Freewheel
Unit"), although I cannot figure out how this engages in 1 and R
speeds.

I also read at various places, that problem could be clogged filter. I
did replace filter not too long time ago.

From all this and the symptoms described, what is the experience
around?

[Tiger]

722.4 transmission is used in 190E cars.

For W140, the only 722.3 transmission were used for diesel models and early
V12 engine. All the other W140 uses 5 speed transmission... which is 722.5.

Are you positive you identified the right transmission for your car? I have
tried searching your car... eurospec W140 to check if it has 4 speed auto
transmission.

[d***@gmail.com]

Post by Tiger
722.4 transmission is used in 190E cars.
For W140, the only 722.3 transmission were used for diesel models and early
V12 engine. All the other W140 uses 5 speed transmission... which is 722.5.
Are you positive you identified the right transmission for your car? I have
tried searching your car... eurospec W140 to check if it has 4 speed auto
transmission.

I realise that this is an old post, but for the sake of someone perusing for information that might read this, I had to chime in and say that this information is not correct. The 722.3xx and 7222.4xx transmission was used in a variety of w140's and 126's, etc. with the 4.2 V8 up through 1993, in fact, my 1992 400se has the 722.3. Please double check your info before posting. D-day

[s***@gmail.com]

Post by Tiger
722.4 transmission is used in 190E cars.
For W140, the only 722.3 transmission were used for diesel models and early
V12 engine. All the other W140 uses 5 speed transmission... which is 722.5.
Are you positive you identified the right transmission for your car? I have
tried searching your car... eurospec W140 to check if it has 4 speed auto
transmission.

I trust by now most have realized that the 5 speed transmission did not appear until mid'95 and latter. Every 140 before that had the same transmission.
To answer the question about the 722.3 and the 722.4 difference- there really isn't a great deal of difference when diagnosing a problem. The 722.3 has less parts as it is a 3speed for most application I believe. I could be incorrect on that but an 80 450 has a 722.3 3speed auto.

[s***@gmail.com]

Post by s***@gmail.com

Post by Tiger
722.4 transmission is used in 190E cars.
For W140, the only 722.3 transmission were used for diesel models and early
V12 engine. All the other W140 uses 5 speed transmission... which is 722.5.
Are you positive you identified the right transmission for your car? I have
tried searching your car... eurospec W140 to check if it has 4 speed auto
transmission.

I trust by now most have realized that the 5 speed transmission did not appear until mid'95 and latter. Every 140 before that had the same transmission.
To answer the question about the 722.3 and the 722.4 difference- there really isn't a great deal of difference when diagnosing a problem. The 722.3 has less parts as it is a 3speed for most application I believe. I could be incorrect on that but an 80 450 has a 722.3 3speed auto.

Correction- I was confusing my 80 SLC with my 82 500SE. The 722.3 is 4speed. Here's a list of trans.
https://en.wikipedia.org/wiki/List_of_Daimler_AG_transmissions

[Tiger]

If you actually does have 722.3 or 4 tranny and no reverse...

http://www.europeantransmissions.com/Bulletin/DTC.merc/97-20.pdf

You just have to replace a part on valve body.

[-]

Hey Tiger, interesting site. Do you have any actual experience with this
company or know of anyone who has used them? Just curious to find out more
information on them.

Thanks!

[Jens]

Hey Tiger, interesting site.  Do you have any actual experience with this
company or know of anyone who has used them?  Just curious to find out more
information on them.
Thanks!

Yes, that must definately be tried before anything else in the next
few days, when I get access to a garage. Are these parts easily
avalible?

Next thing will be replacing B3 piston seals and friction plates. It
seem like it can be done without too much trouble and cost. When it is
open anyway, is there some other recommended things to do?

My diagnose says in any case, that the problem must be associated with
B3 not engaging properly, either because of lack of supply pressure or
because of leaking seals.

[Tiger]

The parts is available anywhere you can get your hand on tranny parts. I
think you are in Denmark.

I would do the valve body before I do anything with B3. Valve body is not
too bad... easily dropped with the pan off.. change required parts, renew
gasket and bolt it back up.

To change B3 friction plates, you have to disassemble the tranny entirely.
It is buried in the middle of the tranny. I have tried to rebuild my tranny
722.3 and It is really buried inside... that if you want to just get to that
part... you might as well rebuild the whole tranny.

[Jens]

Post by Tiger
The parts is available anywhere you can get your hand on tranny parts. I
think you are in Denmark.
I would do the valve body before I do anything with B3. Valve body is not
too bad... easily dropped with the pan off.. change required parts, renew
gasket and bolt it back up.
To change B3 friction plates, you have to disassemble the tranny entirely.
It is buried in the middle of the tranny. I have tried to rebuild my tranny
722.3 and It is really buried inside... that if you want to just get to that
part... you might as well rebuild the whole tranny.

Finally I got the time to investigate further. I took apart the valve
body as suggested with particular attention to the valves/springs
described at the fine link, you provided. Pistons/springs seem OK and
move freely.

Unfortunatlely, I don't have a hydraulic diagram of it, so I can
determine which parts are engaged in reverse and verify their
operation.

After reassembly the transmission still works perfectly in forward,
but no engagement at all in reverse.

I have thought of several options:

The cheapest one is just to concentrate on B3 and associated clutch.
As you say, I might as well overhaul the entire transmission, but that
would also drive up the cost (bands in particular). In both cases I
may come in a situation, where it has all been taken apart and I then
miss a part, which takes days to get (not a good situation, when I
hire space in a workshop).

Then comes the simplest option by getting a used transmission from a
scrap yard. I have found one identical tranmission, but price is much
too high, leading to the most expensive but also most reliable option
of getting a new by Mercedes (at an exhange price with the old
transmission bringing it to a reasonable price... but still much more
expensive).

I am leaning towards the last option.

Any recommendations?

[Tiger]

This post might be inappropriate. Click to display it.

[Jens]

Post by Tiger
Hi Jens,
Bands don't break in transmission and alot of time, they are simply reused
during the rebuild process. The seals are the most importnat thing in the
rebuild process and they tell me that sometime they have to drill out the
rivets in the clutchpack to replace a permanent seal. However, this is
easily checked with sir gun on the clutchpack before you reassemble the
entire tranny.
Don't you have any reasonable wholesale tranny rebuild shop in your country?
It is not much money to rebuild the tranny costwise so some rebuild shop
rather just rebuild and sell many tranny to other shops than to wait for one
customer at a time.  For example, I can get 722.3 tranny for $1250.
So these shop are thinking... okay it cost about $400 to rebuild, part and
laborwise... so if they can make $800 per tranny and sell many fast, it is
big money compared to actual tranny shop who sit a wait for those special
$2000 profit to come in the door. Nowdays in USA, they are asking $2500 to
rebuild 722.3 with only one year warranty.
http://www.autotransparts.com/cart.php?m=product_detail&p=169
I still think your tranny 722.3... this is easily checked by the side metal
stamping right above your tranny oil pan.
Last resort is you buy a junk tranny and rebuild it yourself and then stick
it in your car... but not everyone has the luxury of space and time...
especially space in some countries.

Well, at the time being, the USD exhange rate is low, so on top of
price level in US for these things is already low, the European prices
will appear horrible in comparison.

There is not the same tradition of rebuilding trannys in Europe as in
US (most drive manual transmission). I can have the tranny rebuild,
but I have not been able to find an exhange service anywhere.

Yes, I have seen the US companies selling rebuild trannys at eBay at
1.250 USD. Shipping to Denmark is not feasible though.

A rebuild job in Denmark is around 3.000 USD plus removal/
installation. Compared to have a new tranny at Mercedes at 4.000 USD
(with the old in return), this option is not attractive.

A rebuild kit is around 400 USD. I am very tempted to go this way,
except for the risk of missing parts during the operation and the risk
that it does not cure the problem after all.

I have found one (and just one) junk tranny with exactly the same type
(yes, it is for sure the original 722.368, which was normal for
Europe). It has been driven 200.000 miles, and is priced at some 2.000
USD. Not attractive at all in comparison with the price of a new.

I have then found a 722.362 (for W140 600SE) in Germany also priced at
2.000. It is almost brand new (apparently installed in 2009 and has
only 5.000 miles), and this sounds like a good option, if it will fit.

Do you know, if it is possible to do such exchange (maybe using some
adaption parts from the old tranny)?




I have been looking for rebuild

[Tiger]

All 722.3xx is the same transmission. The only difference is the modulator
valve may be different color and can be swapped to the correct one. The
other difference is the version number... so later version number will have
slightly better response. 722.368 and 722.362 is already the same... version
2 versus version 8... but the 362 is rebuilt so it is already 368 version...
all rebuild will bring up to the latest version assuming the valve body is
rebuilt to spec.

The gearing the same for practical matter. To adapt to different engine and
body style is different rear end differential gear ratio. Do a spec search
on your car and that donor car... you will see the tranmission gear ratio is
all the same.

I have installed a newer 1988 190E tranny into older 1984 190E and it ran
perfect. It actually drove like a 1988 190E. If you look at the tranny part
number... it is also different but they are both 722.4xx tranny. The only
thing I had to change is the output shaft... 1988 had a thicker bigger shaft
(the thing that connects to the flex disc to the drive shaft. You probably
have to do the same but super easily done. Just put a socket on it and
loosen it up (that dimple lock will simply flex back and allows the nut to
loosen up).

I'd go for that low mileage 600SE tranny in your case.

[Jens]

Post by Tiger
All 722.3xx is the same transmission. The only difference is the modulator
valve may be different color and can be swapped to the correct one. The
other difference is the version number... so later version number will have
slightly better response. 722.368 and 722.362 is already the same... version
2 versus version 8... but the 362 is rebuilt so it is already 368 version...
all rebuild will bring up to the latest version assuming the valve body is
rebuilt to spec.
The gearing the same for practical matter. To adapt to different engine and
body style is different rear end differential gear ratio. Do a spec search
on your car and that donor car... you will see the tranmission gear ratio is
all the same.
I have installed a newer 1988 190E tranny into older 1984 190E and it ran
perfect. It actually drove like a 1988 190E. If you look at the tranny part
number... it is also different but they are both 722.4xx tranny. The only
thing I had to change is the output shaft... 1988 had a thicker bigger shaft
(the thing that connects to the flex disc to the drive shaft. You probably
have to do the same but super easily done. Just put a socket on it and
loosen it up (that dimple lock will simply flex back and allows the nut to
loosen up).
I'd go for that low mileage 600SE tranny in your case.

Thanks a lot. I already bought it, and I am looking very much forward
to receive it.

So with this and the old tranny, I can in any case adapt it to the
vehicle. As you say, the modulator may be an issue, and another issue
- if the differential gear ratio is different - the speedometer may
give wrong readings. As well as I can read, the 300SEL has a final
gear ratio of 3,46, whereas the 600SE has 2,65 - a considerable
difference of 23,5%. Any suggestions to this issue other than use the
old parts at the rear of the tranny?

Anyway, I am happy to have taken this decision, since the old tranny
had 500k miles (engine still running perfectly well, all suspension
parts and CV joints replaced etc.). I would have liked to to do the
rebuild - but not the frustration of missing parts in the middle of
the operation.

[Tiger]

You will not have any speedometer problem.

500,000 miles?!

[Jens]

Post by Tiger
You will not have any speedometer problem.
500,000 miles?!

Yes :o)

To my knowledge at least. I know it served its first years as
limousine service. Tax rules are so that they buy it without tax, and
can sell it at market price after 300.000 km in 2 years or 200.000 km
in 3 years. Tax in Denmark is some 180 % in total ("buy one car, pay
for three"), so this is very much where they make their business. And
I know from the dealer, that odometer showed 475.000 km at a service i
1999. The W220 facelift was done in 2000, and I believe that odometer
was reset then. At least it showed 150.000 km when I bought it in
2005, and now it shows 225.000 km. That brings it to at least 700.000
km (438.000 miles).

Anyway, no real problems so far. Tranny problem is probably more due
to age than to mileage, and engine runs smoothly (head was rebuild in
2005). Steering and suspension was a bit sluggish due to worn bushings
and balls, but that has all been replaced.

At the end of the day, I have a car, I really enjoy driving (only
forward though at the moment).

This is how it looks: http://www.benzworld.org/gallery/showgallery.php/cat/all/ppuser/36145

[Tiger]

Wow! A W220 facelift?! Fascinating.

My gosh on your tax system... that's insane.

[DAS]

It leads to relatively low pre-tax prices, accessible to non-residents.

Some years ago, when car prices the UK were relatively high, there was a
lively trade in personal imports from other European countries and even I
brought a Merc in from Germany (in 2001).

I was quite close to doing so from Denmark, but the hassle-factor was much
greater for me, so (probably) paid a little more and bought in Germany.

DAS

To reply directly replace 'nospam' with 'schmetterling'
--

Post by Tiger
Wow! A W220 facelift?! Fascinating.
My gosh on your tax system... that's insane.

[Jens]

Post by DAS
It leads to relatively low pre-tax prices, accessible to non-residents.
Some years ago, when car prices the UK were relatively high, there was a
lively trade in personal imports from other European countries and even I
brought a Merc in from Germany (in 2001).
I was quite close to doing so from Denmark, but the hassle-factor was much
greater for me, so (probably) paid a little more and bought in Germany.
DAS
To reply directly replace 'nospam' with 'schmetterling'

Post by Tiger
Wow! A W220 facelift?! Fascinating.
My gosh on your tax system... that's insane.- Hide quoted text -

- Show quoted text -

Yeah, but the car manufacturers agreed to stop that lower-pre-tax-
price-policy some years ago, so now we pay even more. Politicians are
discussing to lower the tax, but that will give problems for people,
who invested in new cars (drop in market value), so they cannot decide
(how convenient).

[DAS]

I am very sorry to hear that.

Many years ago we had a sudden price drop when a special car tax (about 10%)
was abolished. I don't know to what extent some people suffered, but the
overall effect for us was an improvement.

Now we 'just' have the standard 17.5% VAT on cars, so any price differences
with our near neighbours are probably not so great. More connected with
short-term swings in the EUR: GBP exchange rate.

DAS

To reply directly replace 'nospam' with 'schmetterling'
--
"Jens" <***@minnet.dk> wrote in message news:671b30fa-6c8d-4d73-9678-***@g26g2000yqn.googlegroups.com...
[...]

Yeah, but the car manufacturers agreed to stop that lower-pre-tax-
price-policy some years ago, so now we pay even more. Politicians are
discussing to lower the tax, but that will give problems for people,
who invested in new cars (drop in market value), so they cannot decide
(how convenient).

[Jens]

Post by Tiger
You will not have any speedometer problem.
500,000 miles?!

Yes  :o)
To my knowledge at least. I know it served its first years as
limousine service. Tax rules are so that they buy it without tax, and
can sell it at market price after 300.000 km in 2 years or 200.000 km
in 3 years. Tax in Denmark is some 180 % in total ("buy one car, pay
for three"), so this is very much where they make their business. And
I know from the dealer, that odometer showed 475.000 km at a service i
1999. The W220 facelift was done in 2000, and I believe that odometer
was reset then. At least it showed 150.000 km when I bought it in
2005, and now it shows 225.000 km. That brings it to at least 700.000
km (438.000 miles).
Anyway, no real problems so far. Tranny problem is probably more due
to age than to mileage, and engine runs smoothly (head was rebuild in
2005). Steering and suspension was a bit sluggish due to worn bushings
and balls, but that has all been replaced.
At the end of the day, I have a car, I really enjoy driving (only
forward though at the moment).
This is how it looks:http://www.benzworld.org/gallery/showgallery.php/cat/all/ppuser/36145

Got the new transmission. It is actually brand new (not just a
rebuild) exept for the one year and 8.000 km.

But...... there is a significant difference between 722.368 and
722.362. The mounting face to the engine i way different - no adaption
possible. Of course I didn't notice until I had them side by side. And
the converter of the new one is much larger (makes sense since it is
also for a larger engine).

I'm really in doubt what to do. I could get the overhaul parts,
rebuild the old transmission and try to sell the "new" again. But
still the gears and bearings of the old has 500k miles, and maybe I
will not be able to sell the other.

So, I am getting closer and closer to the conclusion, that I will
transfer the whole inside assembly to the old case, thereby still
having a new one "inside". Unless someone strongly recommends me not
to (I have already been mistaken about the feasibility).

Any suggestions?

[Tiger]

Can't believe the bellhousing difference... bigger engine needs bigger
housing.

http://w126.pp.ru/akp722.pdf

The internals should be the same so I would swap it all out. Do a quick
measurement of the width of the body where all the clutchpacks on the
housing and compare it to the old one.

Check the valve body... should be the same.

[Jens]

Post by Tiger
Can't believe the bellhousing difference... bigger engine needs bigger
housing.
http://w126.pp.ru/akp722.pdf
The internals  should be the same so I would swap it all out. Do a quick
measurement of the width of the body where all the clutchpacks on the
housing and compare it to the old one.
Check the valve body... should be the same.

By looking at partnumbers (through www.detali.ru) it appears as if
internal parts will fit. Planetary assembly, shaft and a few other
parts are different part numbers, but all seals, clutch plates etc.
are the same, so dimensions are necessarily the same. That makes it
worth the try.

The valve body itself and spacer plates have different part numbers,
possibly due to at slightly different hydraulic design or maybe just
due to different shift points. I will be at bit more cautious here.

Unfortunately, I do not have the time until the weekend.

[Jens]

This post might be inappropriate. Click to display it.

[Tiger]

Hi Jens,

I am sorry you had to learn this the hard and expensive way. Perhaps
you can rebuild this 'spare' tranny and recoupe some of your cost.

So, I am assuming you swapped all the parts out of the newer tranny
into your old casing. I can only assume that the springs used in the 600
clutch pack are stronger than the one in your original tranny. Hence, it
shift harder.

I don't know if swapping the vacuum modulator from the newer tranny into
your older one will solve this problem since more powerful engine will have
more torque to 'slip' the clutch pack for smoother shifting.

I should have thought of that different engine has different
bellhousing. When I swapped mine, it was from newer 2.3 190E into older 2.3
190E... so no difference in the housing..

[Jens]

Post by Tiger
Hi Jens,
     I am sorry you had to learn this the hard and expensive way. Perhaps
you can rebuild this 'spare' tranny and recoupe some of your cost.
     So, I am assuming you swapped all the parts out of the newer tranny
into your old casing. I can only assume that the springs used in the 600
clutch pack are stronger than the one in your original tranny. Hence, it
shift harder.
    I don't know if swapping the vacuum modulator from the newer tranny into
your older one will solve this problem since more powerful engine will have
more torque to 'slip' the clutch pack for smoother shifting.
    I should have thought of that different engine has different
bellhousing. When I swapped mine, it was from newer 2.3 190E into older 2.3
190E... so no difference in the housing..

I don't really feel that sorry. In the end, I still have a new gearbox
inside - and gained some more experience.

Meanwhile I've for free got hold on another .358 tranny (same bell
housing as mine), which is leaking but otherwise OK. Now I have plenty
of spares (which I probably won't need), and I may make a rebuild, if
someone should need it.

I checked part numbers on clutch and brake band springs, and they are
the same as for the V12. So harsh (fast) shifting is not due to this.
I cannot say about pistons and springs inside valve body, which could
be different (valve body part number is different although all
channels and connections are identical).

Vaccum Modulator part number is however different (probably providing
different modulating pressure), and since that is exactly what
controls the shift behaviour, I will try to put in the old unit, next
time I get it lifted.

[Tiger]

That's a positive view. I like the way you think. Congrats on your
successful overhaul.

[Jens]

Post by Tiger
Hi Jens,
     I am sorry you had to learn this the hard and expensive way. Perhaps
you can rebuild this 'spare' tranny and recoupe some of your cost.
     So, I am assuming you swapped all the parts out of the newer tranny
into your old casing. I can only assume that the springs used in the 600
clutch pack are stronger than the one in your original tranny. Hence, it
shift harder.
    I don't know if swapping the vacuum modulator from the newer tranny into
your older one will solve this problem since more powerful engine will have
more torque to 'slip' the clutch pack for smoother shifting.
    I should have thought of that different engine has different
bellhousing. When I swapped mine, it was from newer 2.3 190E into older 2.3
190E... so no difference in the housing..

I don't really feel that sorry. Afterall, I still have a new
transmission inside - and gained some more experience.

Of course it would have been nice (very) to have saved the difference
from an overhaul kit to the one I bought. But as you say, maybe
someone needs a rebuild tranny, which I could do (meanwhile I got one
more leaking but otherwise functional .358 tranny for free), or at new
converter for a V12.

Anyway, I checked part numbers of springs for clutches and brake
bands, and they are all the same for .368 and .362. I cannot tell
about pistons and springs inside the valve body, which has a different
part number as a whole, but otherwise is identical in terms of
internal channels, position of valves, connections through the
intermediate plate etc. Thus could give a different shift behaviour.

Vacuum modulator does have different part number and probably a
different modulating pressure range. Since this has exactly the
purpose of matching the shift transition, I will try to swap back to
the old one, next time I get it lifted.

[Wan-ning Tan]

Thanks for the latest status update. In fact, that is the best part of
the discussion, so we know the actual reason of the failure. Many times
we see the symptoms and suggestions but don't know the results.

I have been watching this thread closely, since I also face the question
what to do with my 84 190D transmission. I first found water in ATF
about a years ago. The radiator was immediately replaced. A few months
later, the same milky ATF appeared. The car almost does not move right
now even after fresh ATF. I now suspect rain water though I cannot
determine where it gets into the tranny. I am thinking toward
rebuilding but cannot find much information about "how".

Based on your description, a rebuild does not need special tool. If
removal is the most difficult part, I am sure I can do it (as long as I
can find the time to do it). I do have the ATSG manual.

Post by Jens

Post by Tiger
Can't believe the bellhousing difference... bigger engine needs bigger
housing.
http://w126.pp.ru/akp722.pdf
The internals should be the same so I would swap it all out. Do a quick
measurement of the width of the body where all the clutchpacks on the
housing and compare it to the old one.
Check the valve body... should be the same.

By looking at partnumbers (throughwww.detali.ru) it appears as if
internal parts will fit. Planetary assembly, shaft and a few other
parts are different part numbers, but all seals, clutch plates etc.
are the same, so dimensions are necessarily the same. That makes it
worth the try.
The valve body itself and spacer plates have different part numbers,
possibly due to at slightly different hydraulic design or maybe just
due to different shift points. I will be at bit more cautious here.
Unfortunately, I do not have the time until the weekend.

When swapping parts, I found - of course - that some gaskets (front
cover and rear case in particular) couldn't be reused, and I had to
wait for the parts to arrive. This was exactly the reason (waiting for
parts) why I didn't want to do the repair in first place.
Anyway having the transmission apart I found the reason of the lacking
reverse to be the clutch (brake) friction discs of B3 to be worn down.
I could see by wear marks on the inside of the B3 piston, that the B1/
K1 drum had stopped the B3 piston from engaging B3 - therefor no
reverse.
I was suprised by looking at all the gears and bearings - there was no
visible signs of wear after 750.000 km. Seal material was hard after
20 years of use, but still tight. B1 and B2 brake bands were not as
thick as the new ones, but still plenty of friction material to go the
same distance again. I didn't open K1 and K2 packs (yet) and have
therefor not determined their condition, but they were working well.
Seen in the rear mirror, I should just have done the complete overhaul
in the first place, using the overhaul kit available. It would have
been cheaper and costed less work and worries.... if I had just known
the good shape of the gears.
It was a time consuming job to do (because it was first time I tried),
but it was really not that difficult. Removing/installing the
transmission was in fact much harder.
The lesson learned (and to be shared) is that the gearbox itself will
run forever, and an overhaul with friction discs and all sealings will
give you a virtually new gearbox. Really not a job to be afraid of, as
long as you observe cleanliness during the overhaul.
Now it works well. It shifts a bit too harsh to my taste, although the
vaccum control has been turned fully ccw. There is a relatively heavy
leakage from the place, where the secondary pump is if fitted (not in
my case), which I still have to clear.
Thanks for the help.

[Tiger]

Wherever you get the rebuild kit, you can buy the manual on how to rebuild
it.

I have done rebuilding my 722.3 tranny and it wasn't hard for the work. You
do need some basic tool such as a circlip spreader. I think there is also a
snap ring so a snap ring plier is needed too... cheap at Harbor Freight.

The water damage the friction materials and maybe some seals.

You do need to take time to do this work... I'd spread it over 2 days so
your mind is clear. Friction plates and bands needs to be soaked in ATF for
at least 24 hours if I recalled correctly... unless it is a couple of hours.

[Wan-ning Tan]

Tiger, thanks for the additional info. My confidence is higher after
seeing this thread. Yes, I should have enough tools to do the work. My
wife will probably think I have too many :-)

I look in EPC. There seems to be kit for the internal rebuild, but
shouldn't I also renew the seals or parts in valve body? There are not
many shown in EPC. Another option is I can send it out to MB tranny
specialists. The price I was quoted is $400 - $500 (just the valve
body). Many places offer entire rebuilt tranny around $1500 (plus
around $200 for shipping).

Post by Tiger
Wherever you get the rebuild kit, you can buy the manual on how to rebuild
it.
I have done rebuilding my 722.3 tranny and it wasn't hard for the work. You
do need some basic tool such as a circlip spreader. I think there is also a
snap ring so a snap ring plier is needed too... cheap at Harbor Freight.
The water damage the friction materials and maybe some seals.
You do need to take time to do this work... I'd spread it over 2 days so
your mind is clear. Friction plates and bands needs to be soaked in ATF for
at least 24 hours if I recalled correctly... unless it is a couple of hours.

[Tiger]

That is the delimma for us in USA... we can get cheap rebuild. However, my
experience with Cottman Transmission long time ago was not good. I was young
and maive and they tricked me into a rebuild.

The transmission didn't last... just a little past 1 year warranty. Not
every rebuilder will replace everything that is in the basic rebuild
package. They can buy individual parts and determine what is just needed.
They want to save as much money as possible because 1 year is plenty of time
for the tranny to survive. Hardly anyone rebuild valve body... they probably
just clean it up. What I am saying is they will reuse as many parts as
possible because it is only 1 year.

Transmission shops around here demands $2500 for a rebuild. I can source
$1250 rebuild but no experience with them but they are close by my house.

Rebuild kit can be bought anywhere... no need to specific MB parts. Outfits
like Jaggi will provide you a complete kit for valve body.

Post by Wan-ning Tan
Tiger, thanks for the additional info. My confidence is higher after
seeing this thread. Yes, I should have enough tools to do the work. My
wife will probably think I have too many :-)
I look in EPC. There seems to be kit for the internal rebuild, but
shouldn't I also renew the seals or parts in valve body? There are not
many shown in EPC. Another option is I can send it out to MB tranny
specialists. The price I was quoted is $400 - $500 (just the valve body).
Many places offer entire rebuilt tranny around $1500 (plus around $200 for
shipping).

Post by Tiger
Wherever you get the rebuild kit, you can buy the manual on how to
rebuild it.
I have done rebuilding my 722.3 tranny and it wasn't hard for the work.
You do need some basic tool such as a circlip spreader. I think there is
also a snap ring so a snap ring plier is needed too... cheap at Harbor
Freight.
The water damage the friction materials and maybe some seals.
You do need to take time to do this work... I'd spread it over 2 days so
your mind is clear. Friction plates and bands needs to be soaked in ATF
for at least 24 hours if I recalled correctly... unless it is a couple of
hours.

[Jens]

Tiger, thanks for the additional info.  My confidence is higher after
seeing this thread.  Yes, I should have enough tools to do the work.  My
wife will probably think I have too many :-)
I look in EPC.  There seems to be kit for the internal rebuild, but
shouldn't I also renew the seals or parts in valve body?  There are not
many shown in EPC.  Another option is I can send it out to MB tranny
specialists.  The price I was quoted is $400 - $500 (just the valve
body).  Many places offer entire rebuilt tranny around $1500 (plus
around $200 for shipping).

Post by Tiger
Wherever you get the rebuild kit, you can buy the manual on how to rebuild
it.
I have done rebuilding my 722.3 tranny and it wasn't hard for the work. You
do need some basic tool such as a circlip spreader. I think there is also a
snap ring so a snap ring plier is needed too... cheap at Harbor Freight.
The water damage the friction materials and maybe some seals.
You do need to take time to do this work... I'd spread it over 2 days so
your mind is clear. Friction plates and bands needs to be soaked in ATF for
at least 24 hours if I recalled correctly... unless it is a couple of hours.- Hide quoted text -

- Show quoted text -

@Wan-ning Tan

An overhaul kit from Mercedes is priced at 350$. I don't know exactly
what it contains. Accourding to EPC markings, it is just sealings and
gaskets, but I cannot make it add up to that value.

Anyway, according to the experience I just gained, you should replace
ALL sealings and gaskets, inspect other parts and replace as necessary
(probably nothing needed). I would in any case replace all friction
plates of K1, K2 and B3 - they are not that expensive.

And I would get a couple of brake band thrust pin holders p/n 140 277
01 51. They break easily and cost very little.

[Jens]

Post by Jens

Tiger, thanks for the additional info.  My confidence is higher after
seeing this thread.  Yes, I should have enough tools to do the work.  My
wife will probably think I have too many :-)
I look in EPC.  There seems to be kit for the internal rebuild, but
shouldn't I also renew the seals or parts in valve body?  There are not
many shown in EPC.  Another option is I can send it out to MB tranny
specialists.  The price I was quoted is $400 - $500 (just the valve
body).  Many places offer entire rebuilt tranny around $1500 (plus
around $200 for shipping).

Post by Tiger
Wherever you get the rebuild kit, you can buy the manual on how to rebuild
it.
I have done rebuilding my 722.3 tranny and it wasn't hard for the work. You
do need some basic tool such as a circlip spreader. I think there is also a
snap ring so a snap ring plier is needed too... cheap at Harbor Freight.
The water damage the friction materials and maybe some seals.
You do need to take time to do this work... I'd spread it over 2 days so
your mind is clear. Friction plates and bands needs to be soaked in ATF for
at least 24 hours if I recalled correctly... unless it is a couple of hours.- Hide quoted text -

- Show quoted text -

@Wan-ning Tan
An overhaul kit from Mercedes is priced at 350$. I don't know exactly
what it contains. Accourding to EPC markings, it is just sealings and
gaskets, but I cannot make it add up to that value.
Anyway, according to the experience I just gained, you should replace
ALL sealings and gaskets, inspect other parts and replace as necessary
(probably nothing needed). I would in any case replace all friction
plates of K1, K2 and B3 - they are not that expensive.
And I would get a couple of brake band thrust pin holders p/n 140 277
01 51. They break easily and cost very little.- Hide quoted text -
- Show quoted text -

The ATSG manual is quite detailed in the procedures of dismantling/
reassembling. It refers to some special tools, but in general you can
do without them.

The B2 springs are quite strong, but once you have taken off the valve
body etc., you can use an ordinary large clamp to span accross the
transmission body to compress and remove/fit the spring set.

There is a number of clearances to verify, but in general things
fitted before and will fit again with new K!, K2 and B3 friction
plates (unless bearing, thrust rings etc. are really worn - then you
have an entire different problem than just clearances).

Be careful when taking apart the valve body. Check balls, springs etc.
may fall out. But don't be afraid, if it happens (as it did to me).
The manual is quite accurate in pointing out the locations.

The manual specifies 12 hours for the job (when tranny is out). I
spent some 18 hours on taking apart the two transmissions and
assemling them into one, including a couple of hours to thoroughly
clean the bell housing (to avoid dirt in the assembly work), but
excluding taking apart the clutch packs (they were new from the
donor). Much of the time was spent on reading and understanding the
instructions.

Good luck.

[Wan-ning Tan]

Thanks for the good head-up. I did worry about some of the special
tools mentioned in the ATSG manual. It is great news I don't really
have to use them.

From what you know about the construction of the housing, where do you
think my tranny can get the water from? It is a lot, not just drops. I
estimate there is at least a cup of water mixed in ATF. Radiator was
replaced immediately after the first occurrence. I noticed it again a
few months later while there was no loss of coolant at all. The tranny
does leak (about a liter every 15-20k miles).

TIA

Post by Jens

Post by Jens

Post by Wan-ning Tan
Tiger, thanks for the additional info. My confidence is higher after
seeing this thread. Yes, I should have enough tools to do the work. My
wife will probably think I have too many :-)
I look in EPC. There seems to be kit for the internal rebuild, but
shouldn't I also renew the seals or parts in valve body? There are not
many shown in EPC. Another option is I can send it out to MB tranny
specialists. The price I was quoted is $400 - $500 (just the valve
body). Many places offer entire rebuilt tranny around $1500 (plus
around $200 for shipping).

Post by Tiger
Wherever you get the rebuild kit, you can buy the manual on how to rebuild
it.
I have done rebuilding my 722.3 tranny and it wasn't hard for the work. You
do need some basic tool such as a circlip spreader. I think there is also a
snap ring so a snap ring plier is needed too... cheap at Harbor Freight.
The water damage the friction materials and maybe some seals.
You do need to take time to do this work... I'd spread it over 2 days so
your mind is clear. Friction plates and bands needs to be soaked in ATF for
at least 24 hours if I recalled correctly... unless it is a couple of hours.- Hide quoted text -

- Show quoted text -

@Wan-ning Tan
An overhaul kit from Mercedes is priced at 350$. I don't know exactly
what it contains. Accourding to EPC markings, it is just sealings and
gaskets, but I cannot make it add up to that value.
Anyway, according to the experience I just gained, you should replace
ALL sealings and gaskets, inspect other parts and replace as necessary
(probably nothing needed). I would in any case replace all friction
plates of K1, K2 and B3 - they are not that expensive.
And I would get a couple of brake band thrust pin holders p/n 140 277
01 51. They break easily and cost very little.- Hide quoted text -
- Show quoted text -

The ATSG manual is quite detailed in the procedures of dismantling/
reassembling. It refers to some special tools, but in general you can
do without them.
The B2 springs are quite strong, but once you have taken off the valve
body etc., you can use an ordinary large clamp to span accross the
transmission body to compress and remove/fit the spring set.
There is a number of clearances to verify, but in general things
fitted before and will fit again with new K!, K2 and B3 friction
plates (unless bearing, thrust rings etc. are really worn - then you
have an entire different problem than just clearances).
Be careful when taking apart the valve body. Check balls, springs etc.
may fall out. But don't be afraid, if it happens (as it did to me).
The manual is quite accurate in pointing out the locations.
The manual specifies 12 hours for the job (when tranny is out). I
spent some 18 hours on taking apart the two transmissions and
assemling them into one, including a couple of hours to thoroughly
clean the bell housing (to avoid dirt in the assembly work), but
excluding taking apart the clutch packs (they were new from the
donor). Much of the time was spent on reading and understanding the
instructions.
Good luck.

[Tiger]

Tranny cooler line

Vacuum modulator but it would suck ATF out of tranny.

Tranny pan...

No other way in.unless you got leak but leak woudl leak ATF.

[Jens]

Thanks for the good head-up.  I did worry about some of the special
tools mentioned in the ATSG manual.  It is great news I don't really
have to use them.
 From what you know about the construction of the housing, where do you
think my tranny can get the water from?  It is a lot, not just drops.  I
estimate there is at least a cup of water mixed in ATF.  Radiator was
replaced immediately after the first occurrence.  I noticed it again a
few months later while there was no loss of coolant at all.  The tranny
does leak (about a liter every 15-20k miles).
TIA

Post by Jens

Post by Jens

Tiger, thanks for the additional info.  My confidence is higher after
seeing this thread.  Yes, I should have enough tools to do the work.  My
wife will probably think I have too many :-)
I look in EPC.  There seems to be kit for the internal rebuild, but
shouldn't I also renew the seals or parts in valve body?  There are not
many shown in EPC.  Another option is I can send it out to MB tranny
specialists.  The price I was quoted is $400 - $500 (just the valve
body).  Many places offer entire rebuilt tranny around $1500 (plus
around $200 for shipping).

Post by Tiger
Wherever you get the rebuild kit, you can buy the manual on how to rebuild
it.
I have done rebuilding my 722.3 tranny and it wasn't hard for the work. You
do need some basic tool such as a circlip spreader. I think there is also a
snap ring so a snap ring plier is needed too... cheap at Harbor Freight.
The water damage the friction materials and maybe some seals.
You do need to take time to do this work... I'd spread it over 2 days so
your mind is clear. Friction plates and bands needs to be soaked in ATF for
at least 24 hours if I recalled correctly... unless it is a couple of hours.- Hide quoted text -

- Show quoted text -

@Wan-ning Tan
An overhaul kit from Mercedes is priced at 350$. I don't know exactly
what it contains. Accourding to EPC markings, it is just sealings and
gaskets, but I cannot make it add up to that value.
Anyway, according to the experience I just gained, you should replace
ALL sealings and gaskets, inspect other parts and replace as necessary
(probably nothing needed). I would in any case replace all friction
plates of K1, K2 and B3 - they are not that expensive.
And I would get a couple of brake band thrust pin holders p/n 140 277
01 51. They break easily and cost very little.- Hide quoted text -
- Show quoted text -

The ATSG manual is quite detailed in the procedures of dismantling/
reassembling. It refers to some special tools, but in general you can
do without them.
The B2 springs are quite strong, but once you have taken off the valve
body etc., you can use an ordinary large clamp to span accross the
transmission body to compress and remove/fit the spring set.
There is a number of clearances to verify, but in general things
fitted before and will fit again with new K!, K2 and B3 friction
plates (unless bearing, thrust rings etc. are really worn - then you
have an entire different problem than just clearances).
Be careful when taking apart the valve body. Check balls, springs etc.
may fall out. But don't be afraid, if it happens (as it did to me).
The manual is quite accurate in pointing out the locations.
The manual specifies 12 hours for the job (when tranny is out). I
spent some 18 hours on taking apart the two transmissions and
assemling them into one, including a couple of hours to thoroughly
clean the bell housing (to avoid dirt in the assembly work), but
excluding taking apart the clutch packs (they were new from the
donor). Much of the time was spent on reading and understanding the
instructions.
Good luck.- Hide quoted 9text -

- Show quoted text -

ATF runs through a closed circuit. Generally the ATF is under
pressure, which decreases through the various actuators etc., before
it passes the radiator for cooling (or heating to the operating
temperature of 80C) until it finally arrives to the oil pan again (at
zero relative pressure).

The circuit breathes to the atmosphere through a breather at rear top
of the housing and through the dip stick (leading to the oil pan).

Water will only enter the ATF circuit, when water pressure is higher
than ATF pressure at the point of entry. Or it more or less drips into
the oil pan through the breathing places or another unintended hole
(unlikely - from where should the water come? - I cannot see it,
unless you use the car in some amphibious way).

In the radiator, water is present with a pressure significantly higher
than the ATF passing through. This is true, when the water is hot -
otherwise it is vice versa, and ATF could enter the coolant. This is
still the most likely point of entry, even if you don't see the a drop
in coolant level, and even though you already replaced the radiator
(from where did you get it?).

There is up to three vacuum connections to the tranny: Modulator and
two connections to the throttle position cable (one for Standard/
Economy mode selection if present, and one for delayed upshift when
engine is cold). In all cases they will never carry water (unless your
vacuum circuit is filled with water, which is again more or less
impossible), and they will never provide pressure. Leak in the vacuum
actuator diaphrams would suck out ATF from the tranny and contaminate
your vacuum system, which would be an entire different problem
(happened to me).

Go for the radiator once again.

[Jens]

Post by Jens

Thanks for the good head-up.  I did worry about some of the special
tools mentioned in the ATSG manual.  It is great news I don't really
have to use them.
 From what you know about the construction of the housing, where do you
think my tranny can get the water from?  It is a lot, not just drops.  I
estimate there is at least a cup of water mixed in ATF.  Radiator was
replaced immediately after the first occurrence.  I noticed it again a
few months later while there was no loss of coolant at all.  The tranny
does leak (about a liter every 15-20k miles).
TIA

Post by Jens

Post by Jens

Tiger, thanks for the additional info.  My confidence is higher after
seeing this thread.  Yes, I should have enough tools to do the work.  My
wife will probably think I have too many :-)
I look in EPC.  There seems to be kit for the internal rebuild, but
shouldn't I also renew the seals or parts in valve body?  There are not
many shown in EPC.  Another option is I can send it out to MB tranny
specialists.  The price I was quoted is $400 - $500 (just the valve
body).  Many places offer entire rebuilt tranny around $1500 (plus
around $200 for shipping).

Post by Tiger
Wherever you get the rebuild kit, you can buy the manual on how to rebuild
it.
I have done rebuilding my 722.3 tranny and it wasn't hard for the work. You
do need some basic tool such as a circlip spreader. I think there is also a
snap ring so a snap ring plier is needed too... cheap at Harbor Freight.
The water damage the friction materials and maybe some seals.
You do need to take time to do this work... I'd spread it over 2 days so
your mind is clear. Friction plates and bands needs to be soaked in ATF for
at least 24 hours if I recalled correctly... unless it is a couple of hours.- Hide quoted text -

- Show quoted text -

@Wan-ning Tan
An overhaul kit from Mercedes is priced at 350$. I don't know exactly
what it contains. Accourding to EPC markings, it is just sealings and
gaskets, but I cannot make it add up to that value.
Anyway, according to the experience I just gained, you should replace
ALL sealings and gaskets, inspect other parts and replace as necessary
(probably nothing needed). I would in any case replace all friction
plates of K1, K2 and B3 - they are not that expensive.
And I would get a couple of brake band thrust pin holders p/n 140 277
01 51. They break easily and cost very little.- Hide quoted text -
- Show quoted text -

The ATSG manual is quite detailed in the procedures of dismantling/
reassembling. It refers to some special tools, but in general you can
do without them.
The B2 springs are quite strong, but once you have taken off the valve
body etc., you can use an ordinary large clamp to span accross the
transmission body to compress and remove/fit the spring set.
There is a number of clearances to verify, but in general things
fitted before and will fit again with new K!, K2 and B3 friction
plates (unless bearing, thrust rings etc. are really worn - then you
have an entire different problem than just clearances).
Be careful when taking apart the valve body. Check balls, springs etc.
may fall out. But don't be afraid, if it happens (as it did to me).
The manual is quite accurate in pointing out the locations.
The manual specifies 12 hours for the job (when tranny is out). I
spent some 18 hours on taking apart the two transmissions and
assemling them into one, including a couple of hours to thoroughly
clean the bell housing (to avoid dirt in the assembly work), but
excluding taking apart the clutch packs (they were new from the
donor). Much of the time was spent on reading and understanding the
instructions.
Good luck.- Hide quoted 9text -

- Show quoted text -

ATF runs through a closed circuit. Generally the ATF is under
pressure, which decreases through the various actuators etc., before
it passes the radiator for cooling (or heating to the operating
temperature of 80C) until it finally arrives to the oil pan again (at
zero relative pressure).
The circuit breathes to the atmosphere through a breather at rear top
of the housing and through the dip stick (leading to the oil pan).
Water will only enter the ATF circuit, when water pressure is higher
than ATF pressure at the point of entry. Or it more or less drips into
the oil pan through the breathing places or another unintended hole
(unlikely - from where should the water come? - I cannot see it,
unless you use the car in some amphibious way).
In the radiator, water is present with a pressure significantly higher
than the ATF passing through. This is true, when the water is hot -
otherwise it is vice versa, and ATF could enter the coolant. This is
still the most likely point of entry, even if you don't see the a drop
in coolant level, and even though you already replaced the radiator
(from where did you get it?).
There is up to three vacuum connections to the tranny: Modulator and
two connections to the throttle position cable (one for Standard/
Economy mode selection if present, and one for delayed upshift when
engine is cold). In all cases they will never carry water (unless your
vacuum circuit is filled with water, which is again more or less
impossible), and they will never provide pressure. Leak in the vacuum
actuator diaphrams would suck out ATF from the tranny and contaminate
your vacuum system, which would be an entire different problem
(happened to me).
Go for the radiator once again.- Hide quoted text -
- Show quoted text -

.... and then rebuild the tranny (after having resolved the water
problem) as the leakage indicates anyway.

[Tiger]

No, I have not bought anything from them but I would not have a problem
ordering from them. There is another MB tranny part supplier... Jaggi... do
a search... and same is there... they will supply you parts.

Those prices they quoted on the parts are actually wholesale prices that
tranny shop pays... so you can see how much profit is involved when you are
trained to rebuild tranny. There are some tricks and experience that makes a
difference on a tranny that will last a long time.

On rebuilt transmission, their prices are fair... I can get them even lower
but don't know their reputation... at least they are local to me and they do
offer extended warranty on their tranny. I think last I saw the prices... I
can buy tranny, have them put it in for a hundred or two more than the price
you have seen.

For newer tranny... I think it is like $700 cheaper. Anyway... hope these
info helps.

[Jens]

Post by Tiger
If you actually does have 722.3 or 4 tranny and no reverse...
http://www.europeantransmissions.com/Bulletin/DTC.merc/97-20.pdf
You just have to replace a part on valve body.