DIY 722.9 7G-tronic 7-speed automatic transmission service thread
#276
Super Member
Excellent thread! I plan on doing our trans fluid in the w211 in 4k more miles.
I'm sure I will have questions when I start but from reading the PDF's and seeing other posts/questions this is a very valuable thread!!
:-)
-Nigel
I'm sure I will have questions when I start but from reading the PDF's and seeing other posts/questions this is a very valuable thread!!
:-)
-Nigel
#278
I had a bit of a glitch after doing mine. I took the car for a short drive right away and it seemed to be working fine. The next day I did a 60 mile round trip and noticed that it didn't want to downshift at speed. It would go up through the gears just fine and if I used the paddle shifters I could select any gear, but no amount of throttle input once in high gear would get it to shift.
I got it up to 113F and pulled the drain plug again. An ounce or two of fluid came out. The shift problem has gone away for now. Fingers crossed.
I got it up to 113F and pulled the drain plug again. An ounce or two of fluid came out. The shift problem has gone away for now. Fingers crossed.
#279
So, I just completed the 2nd 722.9 7G transmission service, so I have decided to start a thread and post a DIY write-up.
As most of you know the 722.9 transmission does NOT have a dipstick tube, so checking fluid level via a dipstick is not possible. But, with a few quality tools a moderately competent person can service their own 722.9 transmission and check the level themselves.
The fluid level is checked via an overflow method using a MB STAR Diagnostic system at a specified fluid temperature. If you have access to one, great. If you don't, that is OK, all that is needed is a quality infrared thermometer. I have a MB STAR clone system and have verified that a Fluke 62 infrared thermometer read within 1-2 degrees of what the STAR system does.
Attached are the following documents:
1)722.9 Transmission Service - This is my write-up of how to properly service the 722.9 transmission including all parts and tool needed.
2)Automatic Transmission Oil and Filter Change - This is the latest up to date MB WIS document on how to service the transmission.
3)Automatic Transmission Fluids (ATF sheet 236) - This is the latest up to date MB WIS document on approved ATF.
4)Drain Transmission Fluid from Torque Converter - This is the latest up to date MB WIS document on how to drain the torque converter, which is now required as part of the transmission service.
5)Filling Automatic Transmission with Fluid - This is the latest up to date MB WIS document on filling the transmission and checking fluid level.
6)Oil Pan and Overflow Tube Modified - This is the latest up to date MB WIS document explaining the new updated pan and overflow tube that is required if you have the old out of date pan.
I also have 2 files that are extensively detailed on the design, operation, software, and maintenance. They are posted in the MBWorld Wiki here:
722.9 Study Guide
722.9 Tech Guide
I did not take pictures of the procedure, but took video. I am still trying to process the video. The video portion is just fine, but the sound is horrible and barely legible. I may record a new audio track. I will post the video up when complete. I should be able to add still shots from the video to the write-up at least.
Another thing of note. The WIS document for servicing the transmission floating around on here on MB World is from the STAR DVD's that are available from MB. They are not updated like the WIS documents. So, if you look at the WIS document I posted, you can see MB changed a few things on the service. 1)They added shifting the car into neutral before servicing. 2)A new gasket is required now and can NOT be reused. 3)Draining the torque converter is required as part of the service now.
As most of you know the 722.9 transmission does NOT have a dipstick tube, so checking fluid level via a dipstick is not possible. But, with a few quality tools a moderately competent person can service their own 722.9 transmission and check the level themselves.
The fluid level is checked via an overflow method using a MB STAR Diagnostic system at a specified fluid temperature. If you have access to one, great. If you don't, that is OK, all that is needed is a quality infrared thermometer. I have a MB STAR clone system and have verified that a Fluke 62 infrared thermometer read within 1-2 degrees of what the STAR system does.
Attached are the following documents:
1)722.9 Transmission Service - This is my write-up of how to properly service the 722.9 transmission including all parts and tool needed.
2)Automatic Transmission Oil and Filter Change - This is the latest up to date MB WIS document on how to service the transmission.
3)Automatic Transmission Fluids (ATF sheet 236) - This is the latest up to date MB WIS document on approved ATF.
4)Drain Transmission Fluid from Torque Converter - This is the latest up to date MB WIS document on how to drain the torque converter, which is now required as part of the transmission service.
5)Filling Automatic Transmission with Fluid - This is the latest up to date MB WIS document on filling the transmission and checking fluid level.
6)Oil Pan and Overflow Tube Modified - This is the latest up to date MB WIS document explaining the new updated pan and overflow tube that is required if you have the old out of date pan.
I also have 2 files that are extensively detailed on the design, operation, software, and maintenance. They are posted in the MBWorld Wiki here:
722.9 Study Guide
722.9 Tech Guide
I did not take pictures of the procedure, but took video. I am still trying to process the video. The video portion is just fine, but the sound is horrible and barely legible. I may record a new audio track. I will post the video up when complete. I should be able to add still shots from the video to the write-up at least.
Another thing of note. The WIS document for servicing the transmission floating around on here on MB World is from the STAR DVD's that are available from MB. They are not updated like the WIS documents. So, if you look at the WIS document I posted, you can see MB changed a few things on the service. 1)They added shifting the car into neutral before servicing. 2)A new gasket is required now and can NOT be reused. 3)Draining the torque converter is required as part of the service now.
I have been receiving the error code 200A (fully integrated transmission control (VGS) control unit) is defective in my 2004 E500 with 722.9 transmission. The car is shifting fine, but I don't know if it will start acting up soon. Do you have any information on where to get (aside from MB dealers) and how to change the 722.9 conductor plate? Or maybe there is another fix for this code? Thank you for any insights you may have.
#280
Why is it important to pump the fluid up from the bottom? Wouldn't it be easier to break the locking tab on the fill tube and pour the tranny fluid in, then replace the lock tab?
#282
Senior Member
Not sure which transmission your car has but mine has 722.902 7G-Tronic - see below a page 11 from it's 46 page introduction presentation many years ago.
This thread has very good detailed maintenance instructions for these, starting on page 1. (August 30, 2010)
Happy reading!
![Cheers](https://mbworld.org/forums/images/smilies/cheers.gif)
![](https://cimg4.ibsrv.net/gimg/www.mbworld.org-vbulletin/1221x913/722_9xx_7g_no_dipstick_4a7b6b9ad90affca28ebc7f6b359ae99697b8be1.jpg)
Last edited by arto_wa; 06-24-2017 at 09:40 AM.
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golgi (06-26-2017)
#283
Member
Join Date: Sep 2014
Location: Western MA
Posts: 78
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Received 2 Likes
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2 Posts
2005 CLK500 Convertible
I did the transmission flush with filter change on My 2005 CLK500 convertible. Because my 722.9 doesn't have the TC drain, I flushed it through the upper radiator tran line. I used the garden sprayer ($5 from Walmart) to pump the ATF up. Using Mityvac MVA588 ATF Refill Adapter that I bought on Amazon for around $15. It worked great. Everything went smooth, just time consuming.
After draining and removing the pan I got 4 L. Then I pumped 4 L in. Then flushed 3 times with 2 L out and pumped 2 L in each time. In the last 4th flush I flashed 1 L out (new fluid was already coming out) and pumped 2 L in. So I got total 11 L out and put 12 L in. And then at 45C I had the fluid coming out in constant flow. I used Fuchs Titan ATF 4134.
To measure temperature I used both a digital multimeter with the temp probe taped to the pan and IR thermometer.
After draining and removing the pan I got 4 L. Then I pumped 4 L in. Then flushed 3 times with 2 L out and pumped 2 L in each time. In the last 4th flush I flashed 1 L out (new fluid was already coming out) and pumped 2 L in. So I got total 11 L out and put 12 L in. And then at 45C I had the fluid coming out in constant flow. I used Fuchs Titan ATF 4134.
To measure temperature I used both a digital multimeter with the temp probe taped to the pan and IR thermometer.
#284
Great post John!
I followed this process step by step on my 2008 ML320 CDI with 722.9 G -Tronic Transmission
but got some issues
After draining TC and Transmission pan,
I filled in 9 liters of Fuchs Titan 4134 ATF
Started engine and waited for fluid temp to rise till 45c
Checked temp with my IR thermometer,
opened the drain plug, 800 ml fluid drained and then few drops left dripping out
i closed the plug
left it run for few minutes,
I could hear TC was making small noise initially
After few minutes it got filled and I shifted gear lever few time and TC noise was gone.
I turned off engine,
Next morning I started the engine, drove it around 40 KM and i noticed this noise from TC like
it was empty. It is similar to a noise like bearing running without grease.
and it is hard to accelerate than before and fuel economy is decreased as well since Sunday.
any thoughts ??
Thanks
I followed this process step by step on my 2008 ML320 CDI with 722.9 G -Tronic Transmission
but got some issues
After draining TC and Transmission pan,
I filled in 9 liters of Fuchs Titan 4134 ATF
Started engine and waited for fluid temp to rise till 45c
Checked temp with my IR thermometer,
opened the drain plug, 800 ml fluid drained and then few drops left dripping out
i closed the plug
left it run for few minutes,
I could hear TC was making small noise initially
After few minutes it got filled and I shifted gear lever few time and TC noise was gone.
I turned off engine,
Next morning I started the engine, drove it around 40 KM and i noticed this noise from TC like
it was empty. It is similar to a noise like bearing running without grease.
and it is hard to accelerate than before and fuel economy is decreased as well since Sunday.
any thoughts ??
Thanks
#285
Senior Member
Great post John!
I followed this process step by step on my 2008 ML320 CDI with 722.9 G -Tronic Transmission
but got some issues
After draining TC and Transmission pan,
I filled in 9 liters of Fuchs Titan 4134 ATF
Started engine and waited for fluid temp to rise till 45c
Checked temp with my IR thermometer,
opened the drain plug, 800 ml fluid drained and then few drops left dripping out
i closed the plug
left it run for few minutes,
I could hear TC was making small noise initially
After few minutes it got filled and I shifted gear lever few time and TC noise was gone.
I turned off engine,
Next morning I started the engine, drove it around 40 KM and i noticed this noise from TC like
it was empty. It is similar to a noise like bearing running without grease.
and it is hard to accelerate than before and fuel economy is decreased as well since Sunday.
any thoughts ??
Thanks
I followed this process step by step on my 2008 ML320 CDI with 722.9 G -Tronic Transmission
but got some issues
After draining TC and Transmission pan,
I filled in 9 liters of Fuchs Titan 4134 ATF
Started engine and waited for fluid temp to rise till 45c
Checked temp with my IR thermometer,
opened the drain plug, 800 ml fluid drained and then few drops left dripping out
i closed the plug
left it run for few minutes,
I could hear TC was making small noise initially
After few minutes it got filled and I shifted gear lever few time and TC noise was gone.
I turned off engine,
Next morning I started the engine, drove it around 40 KM and i noticed this noise from TC like
it was empty. It is similar to a noise like bearing running without grease.
and it is hard to accelerate than before and fuel economy is decreased as well since Sunday.
any thoughts ??
Thanks
Sounds like the fluid level is low.
If I am reading your post right, you did not shift through gears after starting the engine and before draining out the .8 liters of fluid - you did only after draining?
If that's the case, it could explain low fluid level.
Last edited by arto_wa; 09-13-2017 at 07:53 AM.
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Nick.who (09-18-2017)
#286
722.9 Transmission Shifting issues
Hi Guys,
I recently did a fluid service on my 722.9 transmission on ML 320, (W164)
Drained TC and pan and I was hoping that will improve shifting.
But actually it did not make any difference.
Shifting is not smooth,
Vehicle has 150k KM on it,
When I opened the pan the oil was not terribly bad, seemed like
it was replaced previously, but one thing I noticed, that
magnets were missing from the pan and fine metallic sludge was mixed in the fluid.
I am wondering if solenoid valves are contaminated with metallic particles causing rough shifting.
After reading different forums on this website, I am suspecting that
those valves may be causing this issue, or something else.
Please help,
THanks
I recently did a fluid service on my 722.9 transmission on ML 320, (W164)
Drained TC and pan and I was hoping that will improve shifting.
But actually it did not make any difference.
Shifting is not smooth,
Vehicle has 150k KM on it,
When I opened the pan the oil was not terribly bad, seemed like
it was replaced previously, but one thing I noticed, that
magnets were missing from the pan and fine metallic sludge was mixed in the fluid.
I am wondering if solenoid valves are contaminated with metallic particles causing rough shifting.
After reading different forums on this website, I am suspecting that
those valves may be causing this issue, or something else.
Please help,
THanks
#287
Super Member
A few points from my recent experience doing this job on a 7G-Tronic Plus:
The filler adapter doesn't have a check valve, so when filling and when done filling, you need a way to block the fluid from coming back out. I used a fluid transfer pump (the kind with two hoses on it - not the kind you screw into a bottle) and when you stop pumping it doesn't all flow out. I put the new fluid into a bucket and pumped from that. (I made sure the bucket was very clean before I started. The hose didn't want to come off the filler adapter when it was time to drain the overflow fluid out, so I just cut it.
This is a job to make sure you are 100% prepared for, and have everything lined up and easy to reach. I had a few mishaps during this job, like the hose popping out of the fluid pump once, and the new (or old) drain plug nowhere to be found when the fluid was 45 degrees. I cut the hose at that point and fluid started coming out, then slowed down. Once I realized I'd misplaced the drain plug, I plugged it back into the pump to stop the flow. By the time I found it, the fluid was up to 62 degrees, so I acted as quickly as possible to swap the plug in. There does seem to be a bit of fluid level tolerance built in, because I am possibly up to 1/4 quart low as a result of my mishap and the transmission is shifting perfectly after the job and 350 miles put on.
Next time I will definitely use the $150 fill tool with the built in shut off valve and make double sure I know where everything is.
I also noticed on this transmission, the pan is a bit tricky to get out and in. There is a metal thing holding wires that blocks access to one of the pan bolts and no obvious way to move/remove it, so I just gently bent it out of the way so I could get to the last pan bolt. When replacing the pan, it helps to put the back of the pan in first then position the front of the pan. I also found the pan gasket likes to jump off, so you have to be very careful of that as well.
Lint free cloth isn't lint free. You really have to watch carefully after you use this to wipe down the pan. There will be little strands left and I just picked them out with my (gloved) fingers.
The filler adapter doesn't have a check valve, so when filling and when done filling, you need a way to block the fluid from coming back out. I used a fluid transfer pump (the kind with two hoses on it - not the kind you screw into a bottle) and when you stop pumping it doesn't all flow out. I put the new fluid into a bucket and pumped from that. (I made sure the bucket was very clean before I started. The hose didn't want to come off the filler adapter when it was time to drain the overflow fluid out, so I just cut it.
This is a job to make sure you are 100% prepared for, and have everything lined up and easy to reach. I had a few mishaps during this job, like the hose popping out of the fluid pump once, and the new (or old) drain plug nowhere to be found when the fluid was 45 degrees. I cut the hose at that point and fluid started coming out, then slowed down. Once I realized I'd misplaced the drain plug, I plugged it back into the pump to stop the flow. By the time I found it, the fluid was up to 62 degrees, so I acted as quickly as possible to swap the plug in. There does seem to be a bit of fluid level tolerance built in, because I am possibly up to 1/4 quart low as a result of my mishap and the transmission is shifting perfectly after the job and 350 miles put on.
Next time I will definitely use the $150 fill tool with the built in shut off valve and make double sure I know where everything is.
I also noticed on this transmission, the pan is a bit tricky to get out and in. There is a metal thing holding wires that blocks access to one of the pan bolts and no obvious way to move/remove it, so I just gently bent it out of the way so I could get to the last pan bolt. When replacing the pan, it helps to put the back of the pan in first then position the front of the pan. I also found the pan gasket likes to jump off, so you have to be very careful of that as well.
Lint free cloth isn't lint free. You really have to watch carefully after you use this to wipe down the pan. There will be little strands left and I just picked them out with my (gloved) fingers.
#288
Senior Member
I used one of these (It has a shutoff valve included):
https://www.idparts.com/motive-power...ro-p-2319.html
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300SE1993 (10-16-2017)
#289
Super Member
I used one of these (It has a shutoff valve included):
https://www.idparts.com/motive-power...ro-p-2319.html
https://www.idparts.com/motive-power...ro-p-2319.html
I also thought about re-using my same setup, but just fitting a shut off valve in line. I am sure I could find something at the plumbing store what would work well.
#290
MBWorld Fanatic!
#291
Super Member
#293
I know I'm very late to this excellent thread but can somebody provide an answer to my query? My car has now reached 109k miles, presumably on the original sump pan. Is it really imperative to change it for the updated unit bearing in mind there have been no issues with the cars gearbox in 14 years? I have read it increases oil flow but what does that actually mean?
#294
Senior Member
I know I'm very late to this excellent thread but can somebody provide an answer to my query? My car has now reached 109k miles, presumably on the original sump pan. Is it really imperative to change it for the updated unit bearing in mind there have been no issues with the cars gearbox in 14 years? I have read it increases oil flow but what does that actually mean?
They must have had a pretty good reason to change the design!
See the enclosed MB service pdf documents for details about the pan, magnets and overflow tube changes.
The two flat magnets should be placed in the sloped area.
Does the AT oil pan in your car have the slope or not?
Last edited by arto_wa; 12-28-2017 at 09:21 PM.
#295
When I found out I did not have a filler tube I knew I needed to do more investigation to find out what I had. I don't know if I have a modified pan or not, I will check. It my question is what actual benefit is there to updating and why? I understand the early pans had magnets installed
#296
Senior Member
![Lightbulb](https://mbworld.org/forums/images/icons/icon3.gif)
When I found out I did not have a filler tube I knew I needed to do more investigation to find out what I had. I don't know if I have a modified pan or not, I will check. It my question is what actual benefit is there to updating and why? I understand the early pans had magnets installed
"The oil pans were first changed to a deeper version at the start of 2004 (these can be identified by the sloped rear end). The new oil pan optimizes oil supply to the transmission in all driving situations.
In addition, the oil filter has been optimized several times to improve the filtration of the transmission oil. Since the new filters also have different dimensions, the oil magnets may have to be repositioned or replaced depending on the type installed."
"Whenever a transmission is removed for repairs, the earlier oil pan (3) with the black overflow tube (4) should be replaced by the new sloped-surface version (1) with the white overflow tube (2)."
The oil-pump suction pickup (it's inside the filter) is submerged little deeper in oil in the modified version - more suction head (NPSH).
"optimizes oil flow in all driving situations" One example is: Less change of reduced oil flow when going up, down or sideways a steep hill.
Last edited by arto_wa; 12-29-2017 at 01:14 PM.
#297
The three pdf documents I posted clearly state:
"The oil pans were first changed to a deeper version at the start of 2004 (these can be identified by the sloped rear end). The new oil pan optimizes oil supply to the transmission in all driving situations.
In addition, the oil filter has been optimized several times to improve the filtration of the transmission oil. Since the new filters also have different dimensions, the oil magnets may have to be repositioned or replaced depending on the type installed."
"Whenever a transmission is removed for repairs, the earlier oil pan (3) with the black overflow tube (4) should be replaced by the new sloped-surface version (1) with the white overflow tube (2)."
The oil-pump suction pickup (it's inside the filter) is submerged little deeper in oil in the modified version - more suction head (NPSH).
"optimizes oil flow in all driving situations" One example is: Less change of reduced oil flow when going up a steep hill.
"The oil pans were first changed to a deeper version at the start of 2004 (these can be identified by the sloped rear end). The new oil pan optimizes oil supply to the transmission in all driving situations.
In addition, the oil filter has been optimized several times to improve the filtration of the transmission oil. Since the new filters also have different dimensions, the oil magnets may have to be repositioned or replaced depending on the type installed."
"Whenever a transmission is removed for repairs, the earlier oil pan (3) with the black overflow tube (4) should be replaced by the new sloped-surface version (1) with the white overflow tube (2)."
The oil-pump suction pickup (it's inside the filter) is submerged little deeper in oil in the modified version - more suction head (NPSH).
"optimizes oil flow in all driving situations" One example is: Less change of reduced oil flow when going up a steep hill.
#298
Member
Two questions
W211 has a trans cooler, is 45c still the right temp for trans level check and should the bottom of the pan be level or the chassis?
Last edited by Shack1; 07-02-2018 at 11:39 PM.
#299
A perfect situation for the application of Yamabond 5. Note: Benz specifically recommend against this so be warned!
In the racing community we have used the Yamabond series of products for sealing gasket free casings where vibration is present for years. Works a treat.
Don't even dream of using crap like Formagasket. It will fail.
In the racing community we have used the Yamabond series of products for sealing gasket free casings where vibration is present for years. Works a treat.
Don't even dream of using crap like Formagasket. It will fail.
Thank you