[SoCalML430]

I have been a member for quite a while and have logged 176K miles on our ML430..This Forum has been my life saver from Transmission fluid change, Engine codes and more.. THANK YOU We love the ML but alas, the transmission finally gave out.. The symptom's -- Move gear lever to any gear and it takes 3- 4K RPMS to get the car to even inch forward, unless you put it in Neutral.. Then it acts like it is in drive... I dropped the pan and there were metal pieces (looks like needle bearing) and enough silver in the fluid to make it extremely thick...

I intend to install an ML500 trans (722.666) (Again thanks to the forum) as a replacement as I can get a good used one with about 75K miles on... But in searching I have run across several very low mileage 722.674. Will the 722.674 swap in? The 722.674 seems to cross reference to the ML500 and AMG55 platform. Since it crosses to those series it would make sense that I could use it in our ML430...

Any help is very much appreciated... It is too sad to see our machine on jack stands...

 

[atmsmshr]

Not sure if I would use any transmission other than an exact match of year and model - trying something different could cause a problem. The last 2 digits in the 722.6xx designation are the engine match. The factory Transmission Control Unit settings are also a consideration.

Car-Part.com may help you with an exact match.

From the ATSG:

Transmission Identification
To utilize the 722.6 transmission behind diesel, 4, 6, 8
and 12 cylinder engines, different gear ratios and torque
capacities are needed. Various ratios are accomplished
in 2 ways:
1. Different size axle ratios in the rear
differential.
2. Different ratio planetary gear sets inside the
transmission.
Various amounts of friction and steel plates are used to
accommodate the required torque capacity through
different heights in the apply piston or snap ring groove
location.
Should an incorrect transmission or rear axle ratio be
installed into the vehicle, the computer system will
observe this as a slipping transmission and produce
implausible ratio error codes.
Should incorrect clutch drums or pistons be used, such
as a 4 cylinder set up behind a 12 cylinder engine,
premature failure of the transmission shall be
experienced.
It is for these reasons that proper identification be
employed when rebuilding or exchanging this unit."

 

[megadamp]

I would second that. It may be possible, but you could unearth a pile of worms.

 

[Mac]

I have been a member for quite a while and have logged 176K miles on our ML430..This Forum has been my life saver from Transmission fluid change, Engine codes and more.. THANK YOU We love the ML but alas, the transmission finally gave out.. ...

'Alas' you say? I have more miles on an our '03 ML500 lifetime tranny with zero ATF changes. Our '02 C320 had more miles on it's lifetime tranny and was taken out by a rear--end collision not lack of ATF changes. Alas, a lifetime is much longer than 176K miles so changing the ATF is not always a 'live saver.'

There are a couple of differences between the 430 and 500 trannies. The gearing because the 500 has more torque and hp (at least the final drive is different). And, the flash memory in the 500 is larger to accommodate a larger program.

 

[atmsmshr]

Many long term MB owners want their transmission serviced, and many on the forum think the 'transmission sealed for life' concept is not in the long term interest of the mechanism.

I asked my local MB dealership Service Advisor what they recommend to help prolong the life of the 722.6 transmission, and they stated a fluid and filter exchange every 40,000 miles would be beneficial, coupled with an adapter replacement. That being said, MB dealer ships use the ATF designed for the 722.9 transmission when servicing the older 722.6 transmissions. Not my preference, but it is allowed by current technical data. http://bevo.mercedes-benz.com/bevoli...&language_id=1

The 40,000 miles interval along with using the spec ATF is the approach I take. However, everyone makes their own judgement and gets to live with the results.

Here is the English from German translation of the service bulleting 'clarifying' the sealed for life position described in our owner's manual.

New M-B bulletin, re: 722.6 & 722.9

In march of 2003, M-B released a bulletin, advising a one-time-only transmission fluid change @ 40 k miles.
This is to remove any particles that may have accumulated during break-in.
At the same time it is also advised to change the fluid on the 4-matic transfer case
****************************************

Circular PW NR. 44/05 NFZ NR. 20/05 24.03.2005 to all Mercedes
Benz partners

Introduction of the transmission oil changing with automatic
transmissions 722,6 and 722,9, as well as with the transfer case of
the 4MATIC-Typen 203/211/220 uniquely with 60.000 km.

Ladies and Gentlemen

A substantial criterion for the customer satisfaction with
automatic transmissions is the shifting quality. This not only in the
newer status of the transmission, but constantly over the entire
Lifecycle.

After the introduction of the optimized lamella package in the
transducer bypass clutch (increase of the number of grooves on 72 to
02/2004) to the long-term stabilization of the switching quality, as
well as, the oil change represents a further step to the conversion of
the NAG1 to the oil used with the NAG2 for switching quality
optimization, in order to hold the switching quality also with high
run performances on a high level. In the oil stored particle is
removed by the unique oil change, whose entry takes place to a large
extent into the first 40'000 km and it can have impairments of the
comfort of the switching quality why a unique (and not in turn) oil
change was determined.

For this the again developed transmission oil ATF3353 (AO019894503)
makes an additional contribution that we fill in automatic
transmission 722,9 since serienanlauf, with these automatic
transmissions from house. In the transfer case of the 4MATIC-Typen
203/211/220 the oil 001,989 2303 is used, in order to likewise hold
the comfort self-shadows of the 4MATIC-Systems high level with the
change.

Deviating of it a transmission oil changing with the oil FOX ATF 28
(AOO19894603), developed particularly for it, is to be executed
starting from introduction with the transmission 722,8 (Autotronic,
type 169) all 60,000 km.

For vehicles with ASSYST the service position was already taken up to
the maintenance scopes. We will extend the service pages by the note
starting from FIN XXXXXXXXX, are evident starting from WIS update
03,05 the corrected service pages. For vehicles with ASSYST plus is
caused the service position to the service page automatically by the
maintenance computer. The modification of the data records necessary
for it is only possible starting from data record release 09,2005.

 

[4wd430]

It would be cool if a 55 AMG tranny could be used

 

[Mac]

Many long term MB owners want their transmission serviced, and many on the forum think the 'transmission sealed for life' concept is not in the long term interest of the mechanism....etc., etc.

That said--e.g., various bulletins dating back to 2005-- for more recent thinking keep in mind that the manual for the 2008 C300, for example, has but a single ATF change at about 30K miles...

The tranny engineers establish the spec. The service mechanics want work. So, MB goes back and forth. many manufacturers of high quality autos refuse to go back and forth--e.g., Lexus still has a lifetime tranny.

 

[gsfent]

So, MB goes back and forth. many manufacturers of high quality autos refuse to go back and forth--e.g., Lexus still has a lifetime tranny.

BMW had the same lifetime tranny fill requirement----until they stopped providing for "free" maintenance.

Every one does what they feel is best. But I don't believe the fluids are designed to last forever.

So I typically change tranny and diff fluids around 50-60k miles. For the average driver that is every 3-4 years. And it is DIY if you don't fee like paying (although I recommend letting someone do the tranny so you can get the fluid our of the torque converter too). Pretty cheap insurance to maintain some expensive (transmission) parts.

Of course, YMMV.

Regards,
Jerry

 

[Mac]

BMW had the same lifetime tranny fill requirement----until they stopped providing for "free" maintenance.

Every one does what they feel is best. But I don't believe the fluids are designed to last forever.

So I typically change tranny and diff fluids around 50-60k miles. For the average driver that is every 3-4 years. And it is DIY if you don't fee like paying (although I recommend letting someone do the tranny so you can get the fluid our of the torque converter too). Pretty cheap insurance to maintain some expensive (transmission) parts.

Of course, YMMV.

Regards,
Jerry

The only logic that makes any sense is that it all begins with transmission and ATF engineers. They arrive at science-based decisions about all of the issues. Only after the science and bench-testing and years of experience do the beliefs of consumers come into play. And the some consumers can be swayed by those who may have personal interests in second-guessing the engineers. Mechanics want to be paid to change ATF fluid and is easy for them to say they know more about your transmission and the ATF in it than the German engineers that designed it. And then, you know how old superstitions die hard. One of them is that you don't put new wine in old skins. And, it's like the global warming debate. For some, science just does not matter. It's all just taken on faith. For example, the AGW debate morphed into the climate change debate. But climate always changes so that morphed into disastrous climate disruption debate. So now, even if there is cold weather someone will point to that as evidence of global warming. Undoubtedly, there still are people who change their engine oil every 2,000 miles. Maybe... there was a time that made sense, such as before advances in filtration the move to synthetics and when the engine was a four cylinder that had been converted to automobile use from a British tank.

 

[SoCalML430]

Trans has been installed etc

I really appreciate the feedback from the initial message and wanted to let anyone who is interested the results. We did get the 2002 ML500 trans delivered..it came with a torque converter (no drain plug) so I tipped it up and drained as much as I could... Added 1 quart of fresh fluid and repeated. 2 more time The last swap the fluid came out just about as clear and clean as it went in. .. I changed the input shaft seal, Put together a Ghetto flush system to clear out the transcooler ( Ran 3 quarts of fluid through it... The final quart I strained through some cheese cloth to see if any particles/ dirt or debri were left. (We were good..) When I had the ML430 Trans next to the ML500 trans everything looked identical, except the shift linkage. I choose to modify the shift rod and not move the connection on the trans. After lots of patience, I got the ML500 trans mounted up and got everything buttoned up. I do not have access to a lift so all of this was accomplished on my garage floor. I had to get safely creative to lift the truck high enough to move the trans in and out from beneath the vehicle. Once I got everything buttoned up, I had to adjust the shift rod by cutting about 3/4 of inch to have it meet up with the trans linkage on the ML500 trans. I used carsoft to clear the trans code and a generic OBD to clear the CEL.. Poured in the fluid about 8 qts to get it going ( prepared with the dipstick in hand) ... Started it up with carsoft running Code 98 popped up even after checking the connector etc. After some checking found that I had to replace the conductor plate. Ultimately I found that the trace for the 1-2 3-4 shift solenoid was intermittent. I should of checked the connections before adding all that fluid... Just a short detour, and thank goodness for the forum I was able to search and find the proper testing sequence.

We have put about 1200 miles on the vehicle since the swap. No CEL, or any codes...and the trans is shifting great. Basically, other than the part number stamped on the transbody and the shift linkage on the trans, the units matched up perfectly. We did reset the adaptive drive system, but no programming was needed for the ETC and perhaps I just got lucky but the swap worked for me. I will change out (just pan and filter change) fluid at 1500 miles and see where we are at.

Thank you again...