Alex Conder

Well, she is all back together. Everything seems to be running just fine and the shudder is gone. I put her through a some pretty good paces -- heavy acceleration through all the gears multiple times and lots of interstate speed downshifts. Barring it being just a fluke that the shudder didn't present itself on this test, I'd say its fixed. I did not epoxy the small piece of plastic that was broken -- the range selector lever controls the manual valve perfectly. Thanks for all the help everyone!

Mud

Good deal. I'm going to be rebuilding a TH400 after the holidays - after getting a basic understanding of the complexities and controls of the MB transmission, doing the 400 seems like caveman work lol. But .... I must say that dinosaur did last since 1984.
On my E350, I had paid the dealer for fluid/filter service at 30k miles - in my case the cost was $325 and I was ok with that. Car is at 50k miles now and under ELW till 100k so I wanted to document transmission service even though I do most other maintenance. One other reason is that refill seems pretty fiddly, I take it you did that without issue?

Alex Conder

$325 is a steal! I would have hopped on that in a second.

Refill is not bad, most people either use a pump or compressed air. I used gravity fill, just had a funnel about chest height and it slowly equalized and filled the transmission as I poured it in. The fill rig I made using 3/8" I.D plastic tubeing from Lowes along with two $4 ball valves from lowes and a T-union. One part of the T goes to the pan, the other end to the fill funnel via a valve and the other end has the other valve and is used to drain for level check. This seems wordy, I can post a picture in a little while.

Oda112

Good job man! I'm glad to hear everything is working properly and you're free of the shudder. Did you clean the screens of the valves and the sandwich gasket on the valve body too? I'm curious to see how mine will look like, hopefully by this time next week I will have finished the job too.

Mud

Thank you for the info , I wasn't sure how to get the level right 👍
Oda, that's a good parts diagram - saved! Good question on the solenoid screens, they were shown to be a common cause of comm error with TCU. Debris clogging the screens.

Alex Conder

I took out all of the solenoids and inspected the screens. None were damaged and all were pretty clean. I used a magnet to collect any debris in the screen and effectively none was removed. I expected them to be in worse shape. As for the sandwich gasket are you talking about between the valve body/tcu and the casing or the two halves of the valve body? I did not take the complete valve body apart and pull out the individual valves. I considered it -- ended up not doing it because of how clean the solenoid screens were. The valve body/tcu had no gasket where it mated to the casing.

Oda112

That's good news, seems like you should get a long, good use out of this gearbox. Yes, I was referring to the two halves of the valve body, I've seen a youtube video of a complete teardown and rebuild of the 722.9 and the guy there replaced that gasket as well. His had some gray , gooey deposits and his solenoid valves intake port screens were pretty nasty (flakes of metal) so I'm guessing that's why he replaced it.

Oda112

Hey Alex! My parts are going to be here soon for my tranny fluid change. What should I look for if I wanted to break off the same little plastic thing you did? Also, everything good with the new fluid?

belarus27

Do you guys do the work in your driveway/garage or at a shop? That seems like a job that will require a lift i would imagine , regular jacks wont do it. Plus in addition gotta hsve the right tools
Just curious

Oda112

I will attempt it in my garage, I have decent jack stands, they lift up to 21 inches, that's more than enough. The only thing you can't manufacture yourself with readily available materials is the transmission adapter filler plug, for the rest you just need basic tools. A pressure filler like the Schwaben 3l manual pump or the 3l OemTools one are better and relatively cheap options if you want to make the job easier or you can just use gravity like OP.

Alex Conder

Hey sorry I kind of disappeared. Everything is still good to go. To avoid breaking the piece I did, don't fiddle with the manual valve and be gentle if you do. I had my car up on jacks at all 4 corners. Now fighting an Airmatic issue

Oda112

I ended up not playing with it for now, I'll attempt to clean the solenoid screens and valve body next time I change my ATF fluid. I did find a curious thing in the tranny oil pan, there was an extra overflow pipe floating in there. Maybe it's a customary thing for MB techs to do, IDK, what do you think?
Also, I seem to be having to do the same repairs as you, a few days after yours occur. I think our cars are malfunction synced buddies, I'm having an Airmatic issue too The cold weather defeated my Airmatic, this thing is officially behaving like an old arthritic hag, it almost left me stranded on the east coast.

Alex Conder

Its about time to get rid of this thing

Oda112

Not yet, I like a challenge. Also, it hasn't left me stranded yet, it was close, but I can't fault it for that.

belarus27

that is love ☺