DIY 722.9 7G-tronic 7-speed automatic transmission service thread - MBWorld.org Forums

Go Back  MBWorld.org Forums > Mercedes-Benz Sedans > C-Class (W203)
DIY 722.9 7G-tronic 7-speed automatic transmission service thread >

DIY 722.9 7G-tronic 7-speed automatic transmission service thread

Notices
C-Class (W203) 2001-2007, C160, C180, C200, C220, C230, C240, C270, C280, C300, C320, C230K, C350, Coupe

DIY 722.9 7G-tronic 7-speed automatic transmission service thread

Old 08-30-2010, 12:34 PM
  #1  
Super Moderator
Thread Starter
 
johnand's Avatar
 
Join Date: Dec 2006
Location: Camas, WA
Posts: 2,339
Thanks: 0
Thanked 15 Times in 4 Posts
2007 C230SS; 2014 ML350 BT
DIY 722.9 7G-tronic 7-speed automatic transmission service thread

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latest up to date MB WIS document explaining the new updated pan and overflow tube that is required if you have the old out of date pan.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.

Last edited by johnand; 02-22-2014 at 12:03 PM.
johnand is offline  
The Following 12 Users Say Thank You to johnand For This Useful Post:
arto_wa (08-22-2016), Celicasaur (02-14-2018), Faniskogen (09-22-2016), Kamal63 (01-19-2018), madalitso (09-13-2017), magjistari (08-22-2016), maxoujm (09-28-2018), Nick.who (09-12-2017), ponderingnugget (06-19-2017), rocketship (05-20-2018), srmauer (07-10-2017), WOT48 (08-09-2017)
Old 08-30-2010, 12:37 PM
  #2  
Super Moderator
Thread Starter
 
johnand's Avatar
 
Join Date: Dec 2006
Location: Camas, WA
Posts: 2,339
Thanks: 0
Thanked 15 Times in 4 Posts
2007 C230SS; 2014 ML350 BT
When I went to replace my fuel filter this weekend, I noticed my transmission pan was leaking. So, I have been talking to Glyn via PM about it. I am pretty sure, it is because I didn't clean the new gasket, and I used disposable shop towel, even though I used compressed air to blow them off.

I can't stress enough, that all sealing surfaces must be SPOTLESSLY CLEAN. MB WIS recommends using chamois leather to clean the surfaces. I would follow that recommendation.

Last edited by johnand; 08-30-2010 at 01:06 PM.
johnand is offline  
Old 08-30-2010, 07:28 PM
  #3  
Senior Member
 
Join Date: Jun 2007
Location: cincy-oh
Posts: 322
Thanks: 0
Thanked 1 Time in 1 Post
07 c230SS
how many miles do you have?
jogger is offline  
Old 08-30-2010, 07:36 PM
  #4  
Super Moderator
 
Glyn M Ruck's Avatar
 
Join Date: Jun 2008
Location: Llandudno, Cape Town, South Africa
Posts: 19,893
Thanked 76 Times in 64 Posts
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
Excellent post John. This should be a reference for the entire board.
Glyn M Ruck is offline  
Old 08-30-2010, 07:46 PM
  #5  
MBWorld Fanatic!
 
C230 Sport Coup's Avatar
 
Join Date: Jun 2002
Location: Bay Area
Posts: 6,257
Thanked 49 Times in 47 Posts
C230 Sport Coup & W164 ML350
Hey, how come you got a TC drain screw and I don't?
I see you put the pdf's I sent you long ago to good use.
C230 Sport Coup is offline  
Old 08-31-2010, 09:26 AM
  #6  
Super Moderator
 
Glyn M Ruck's Avatar
 
Join Date: Jun 2008
Location: Llandudno, Cape Town, South Africa
Posts: 19,893
Thanked 76 Times in 64 Posts
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
Because the TC drain plug was removed from the 722.6 in mid 1999. First 722.9 tranny's did not have one. It was reintroduced later I am informed.
Glyn M Ruck is offline  
Old 08-31-2010, 11:41 AM
  #7  
Super Moderator
Thread Starter
 
johnand's Avatar
 
Join Date: Dec 2006
Location: Camas, WA
Posts: 2,339
Thanks: 0
Thanked 15 Times in 4 Posts
2007 C230SS; 2014 ML350 BT
Originally Posted by C230 Sport Coup View Post
Hey, how come you got a TC drain screw and I don't?
I see you put the pdf's I sent you long ago to good use.
Because I am special and have a 7G transmission

Todd, yes I did put the PDF's to good use. But, now I am spoiled with WIS.net, because I have the updated PDF's and not the old ones that are on the MB STAR DVD's Let me know if I can return the favor by getting you any updated documents you want.
johnand is offline  
Old 08-31-2010, 11:43 AM
  #8  
Super Moderator
Thread Starter
 
johnand's Avatar
 
Join Date: Dec 2006
Location: Camas, WA
Posts: 2,339
Thanks: 0
Thanked 15 Times in 4 Posts
2007 C230SS; 2014 ML350 BT
Originally Posted by jogger View Post
how many miles do you have?
75K. I had the dealer do the 1st service at 36K.

I change mine around every 36K as is the recommended interval for ROW. I plan on keeping my car for several 100K miles.
johnand is offline  
Old 08-31-2010, 05:27 PM
  #9  
MBWorld Fanatic!
 
C230 Sport Coup's Avatar
 
Join Date: Jun 2002
Location: Bay Area
Posts: 6,257
Thanked 49 Times in 47 Posts
C230 Sport Coup & W164 ML350
Ooooo! Well, if you could find me something on wheel bearing packing and replacing, front and rear, and the type of gease needed, well, that would be helpful.
I have some bearing issues I need t deal with,
and hadn't found just the right info yet.
2002 203.747 on WIS.

Originally Posted by johnand View Post
Because I am special and have a 7G transmission

Todd, yes I did put the PDF's to good use. But, now I am spoiled with WIS.net, because I have the updated PDF's and not the old ones that are on the MB STAR DVD's Let me know if I can return the favor by getting you any updated documents you want.
C230 Sport Coup is offline  
Old 09-01-2010, 02:50 AM
  #10  
MBWorld Fanatic!
 
W203E35's Avatar
 
Join Date: Feb 2009
Posts: 5,537
Thanks: 0
Thanked 3 Times in 3 Posts
2006 C350 Sport 6MT
John, thanks brother. I'm at 48k and will definetly need an Oil and filter change soon.

Thanks again


John Anderson
W203E35 is offline  
Old 09-01-2010, 09:15 AM
  #11  
Super Moderator
Thread Starter
 
johnand's Avatar
 
Join Date: Dec 2006
Location: Camas, WA
Posts: 2,339
Thanks: 0
Thanked 15 Times in 4 Posts
2007 C230SS; 2014 ML350 BT
Originally Posted by Karo View Post
John, thanks brother. I'm at 48k and will definetly need an Oil and filter change soon.

Thanks again


John Anderson
You are more than welcome bud. New job keeping you busy huh? Haven't heard from you here much lately.
johnand is offline  
Old 09-01-2010, 10:30 PM
  #12  
Junior Member
 
viku_st's Avatar
 
Join Date: Apr 2009
Location: seattle, wa
Posts: 59
Thanks: 0
Thanked 0 Times in 0 Posts
E500 AMG Pkg 2004, C230K M111
Originally Posted by johnand View Post
When I went to replace my fuel filter this weekend, I noticed my transmission pan was leaking. So, I have been talking to Glyn via PM about it. I am pretty sure, it is because I didn't clean the new gasket, and I used disposable shop towel, even though I used compressed air to blow them off.

I can't stress enough, that all sealing surfaces must be SPOTLESSLY CLEAN. MB WIS recommends using chamois leather to clean the surfaces. I would follow that recommendation.
Hey John, good post!!!

When I chenged my ATF, I barely lubricated the transmission surface, so the gasket would sits better(as I say "will find its own place"), just barely, like oil dust, no more. So far, few mounths later no leaks. and did the same way on my C230 with 722.6 a while ago,- looks clean. And I followed the same WIS instructions.
Thanks for the contribution to this forum

Last edited by viku_st; 09-01-2010 at 10:33 PM.
viku_st is offline  
Old 09-02-2010, 07:43 AM
  #13  
Super Moderator
 
Glyn M Ruck's Avatar
 
Join Date: Jun 2008
Location: Llandudno, Cape Town, South Africa
Posts: 19,893
Thanked 76 Times in 64 Posts
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
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.
Glyn M Ruck is offline  
Old 09-02-2010, 04:27 PM
  #14  
Super Moderator
Thread Starter
 
johnand's Avatar
 
Join Date: Dec 2006
Location: Camas, WA
Posts: 2,339
Thanks: 0
Thanked 15 Times in 4 Posts
2007 C230SS; 2014 ML350 BT
Thanks viku_st for the information. Since my pan has a tendency to leak, (Had it in twice to the dealer under warranty for leaking.) I ordered a new pan, new gasket, standoff pipe, drain plug, drain plug washer, and pan bolts from parts.com for just over $50.

My current pan is the updated beveled pan with white standoff part number A2202700912. But, EPC says that part is replaced by A2212701212. So, it appears the pan was updated again, so I figured, I would get the latest pan. Maybe there was a defect with my pan.

Also, my gasket came unpacked from RM European and was sitting on my bench for a few weeks. I failed to clean it at all before installing on the pan. I bet is had some dirt/debris on it.
johnand is offline  
The Following User Says Thank You to johnand For This Useful Post:
madalitso (09-13-2017)
Old 09-02-2010, 10:55 PM
  #15  
Super Moderator
 
splinter's Avatar
 
Join Date: Jul 2006
Location: Orange County, CA
Posts: 3,354
Thanks: 0
Thanked 5 Times in 5 Posts
GMC - Miata - Trek
Excellent DIY, johnand. Appreciate you sharing your expertise.
splinter is offline  
Old 09-07-2010, 02:34 AM
  #16  
MBWorld Fanatic!
 
W203E35's Avatar
 
Join Date: Feb 2009
Posts: 5,537
Thanks: 0
Thanked 3 Times in 3 Posts
2006 C350 Sport 6MT
Originally Posted by johnand View Post
You are more than welcome bud. New job keeping you busy huh? Haven't heard from you here much lately.
Extremely busy, so busy that I worked today on Labor Day

Hows the home projects going? I saw your remodeling now By the way the backyard came along nicely (my comment is a little late ). You got great skills
W203E35 is offline  
Old 09-09-2010, 06:37 PM
  #17  
Junior Member
 
gild's Avatar
 
Join Date: Nov 2009
Posts: 37
Thanks: 0
Thanked 0 Times in 0 Posts
'10 E550 Coupe, '67 230 SL, '06 E350 4-Matic, '75 911S, '04 Porsche Boxster S, '04 Cayenne Turbo
OUTSTANDING writeup! I just finished my fluid change following your step by step process with no issues except letting the temperature get past me. Had to wait for it to cool down and start over. Other than that everything went smoothly. It ended up taking about eight liters with only a small amount rejected.

Thanks!
gild is offline  
Old 09-09-2010, 07:08 PM
  #18  
Super Moderator
Thread Starter
 
johnand's Avatar
 
Join Date: Dec 2006
Location: Camas, WA
Posts: 2,339
Thanks: 0
Thanked 15 Times in 4 Posts
2007 C230SS; 2014 ML350 BT
Originally Posted by gild View Post
OUTSTANDING writeup! I just finished my fluid change following your step by step process with no issues except letting the temperature get past me. Had to wait for it to cool down and start over. Other than that everything went smoothly. It ended up taking about eight liters with only a small amount rejected.

Thanks!
Awesome! Glad I could help

The fluid does heat up fast if it hasn't sat overnight.
johnand is offline  
Old 09-15-2010, 01:31 PM
  #19  
Super Moderator
Thread Starter
 
johnand's Avatar
 
Join Date: Dec 2006
Location: Camas, WA
Posts: 2,339
Thanks: 0
Thanked 15 Times in 4 Posts
2007 C230SS; 2014 ML350 BT
So, I just got done draining the fluid and dropping the pan. Again, I made a nice ATF mess. Even with the drain plug and standoff removed there is over a liter of fluid in the pan, and you have to tip it away from the rear slightly to remove it. So, once again, I have a nice mess off ATF

I cleaned the NEW pan, NEW gasket, and transmission housing with a new microfiber cloth. Tried the leather chamois, and it left a bunch of lint behind So, after cleaning with the microfiber I blew everything off with compressed air. I then proceeded to bolt up the pan. Here is where I think I screwed up last time. There was 2 sprags, that weren't quite touching the transmission housing on the outside edge before I pulled the pan. This time I was VERY careful in making sure all the sprags were correctly seated on the pan. I did this by putting the 2 center sprags and bolts on loose enough just to hold the pan in place. Then I had to wiggle and push the pan toward the rear of the car to get the pan and sprags to seat correctly. The rear of the pan gasket touches the bracket for the transmission mount, and the gasket needs to be compressed slightly against it. I noticed this the 1st time I put the pan up, but didn't push the pan toward the rear while putting the sprags and bolts in, and remember the front 2 were a little difficult to hand tighten the bolts. By pushing the pan toward the rear while hand tightening the bolts seemed to work much better this time.

Now I just need to fill with fluid and adjust the level. Then I will report back on if that worked to stop the leak.

Gild did you have that interference problem with the pan and trans mount?
johnand is offline  
Old 09-15-2010, 02:29 PM
  #20  
Junior Member
 
gild's Avatar
 
Join Date: Nov 2009
Posts: 37
Thanks: 0
Thanked 0 Times in 0 Posts
'10 E550 Coupe, '67 230 SL, '06 E350 4-Matic, '75 911S, '04 Porsche Boxster S, '04 Cayenne Turbo
Originally Posted by johnand View Post
Gild did you have that interference problem with the pan and trans mount?
No, on the GL there is plenty of room all around the pan to work and visually inspect. It did make a huge mess though because there was so much fluid left in the pan after draining. I was able to change my W211 5-speed fluid without hardly a drip.
gild is offline  
Old 09-17-2010, 09:54 AM
  #21  
Super Moderator
Thread Starter
 
johnand's Avatar
 
Join Date: Dec 2006
Location: Camas, WA
Posts: 2,339
Thanks: 0
Thanked 15 Times in 4 Posts
2007 C230SS; 2014 ML350 BT
Originally Posted by gild View Post
No, on the GL there is plenty of room all around the pan to work and visually inspect. It did make a huge mess though because there was so much fluid left in the pan after draining. I was able to change my W211 5-speed fluid without hardly a drip.
Nice that the GL has more room the W203 is very tight in the rear area.
johnand is offline  
Old 09-17-2010, 10:02 AM
  #22  
Super Moderator
Thread Starter
 
johnand's Avatar
 
Join Date: Dec 2006
Location: Camas, WA
Posts: 2,339
Thanks: 0
Thanked 15 Times in 4 Posts
2007 C230SS; 2014 ML350 BT
I am convinced my car hates me. So, I crawled under the car yesterday after a drive to and from work and there was some ATF on front part of the pan and seal

Though, it appears it is not the pan that is leaking When I changed the fluid, I drained the torque converter as is recommended now by MB. The problem with draining it is the torque converter drain plug is at and angle in relation to the access hole. So, when you pull the drain plug, the ATF drips down into the bell housing. There is little to no clearance to get rags in there to clean it up. So, what is leaking, is the fluid that got trapped in the bell housing while draining the torque converter. I would recommend when people drain the torque converter, to make some kind on shield, or just rags to soak up the ATF before it pools in the bell housing.

Wish I could edit my 1st post, so I could update the PDF with these observations.
johnand is offline  
Old 09-17-2010, 06:24 PM
  #23  
MBWorld Fanatic!
 
Join Date: Jul 2008
Posts: 6,743
Thanked 28 Times in 26 Posts
2014 C350 Sport Sedan & 2015 Kia Optima Hybrid EX
Originally Posted by johnand View Post
the W203 is very tight in the rear area.
But this is always a desirable trait...
LILBENZ230 is offline  
Old 09-18-2010, 08:43 AM
  #24  
Super Moderator
Thread Starter
 
johnand's Avatar
 
Join Date: Dec 2006
Location: Camas, WA
Posts: 2,339
Thanks: 0
Thanked 15 Times in 4 Posts
2007 C230SS; 2014 ML350 BT
Originally Posted by LILBENZ230 View Post
But this is always a desirable trait...
Was wondering when someone would take that out of context.
johnand is offline  
Old 09-18-2010, 09:20 PM
  #25  
Super Moderator
 
Glyn M Ruck's Avatar
 
Join Date: Jun 2008
Location: Llandudno, Cape Town, South Africa
Posts: 19,893
Thanked 76 Times in 64 Posts
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
Karo & Patrick -
Glyn M Ruck is offline  

Thread Tools
Search this Thread
Rate This Thread
Rate This Thread:
You have already rated this thread Rating: Thread Rating: 7 votes, 5.00 average.

Quick Reply: DIY 722.9 7G-tronic 7-speed automatic transmission service thread


Contact Us Archive Advertising Cookie Policy Privacy Statement Terms of Service

© 2018 MH Sub I, LLC dba Internet Brands

We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.
 
  • Ask a Question
    Get answers from community experts
Question Title:
Description:
Your question will be posted in:
You Rated this Thread: 5