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I didn't drive it to see if it can upshift. I just put it in B and 2 and noticed it will go forward and it wouldn't just rev like 3 and D. But I could try that around the neighborhood and see what happens.Will it drive normally in B and 2? If so, what happens when you try to let it upshift? Had you made any changes to the transmission (service, etc) in the last few hundred or few thousand miles?
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Thanks for your input, sir!Hrmmm. That is strange!
Any chance you have a spare valve body to swap in for testing? If not, you likely have two options. 1 - remove your VB and open each of the side plates to inspect for any damaged springs or other visible failures inside the VB. Or, B... shell out for a Sun Valley reman transmission. For test purposes, even a SGS VB (from a 140 chassis) would suffice. Gotta be some at your Pick+Pull.
It's REALLY difficult to diagnose internal transmission problems. Having a spare VB helps a lot, if you have previously installed/tested to confirm it's good - if there's no change with the spare VB, the problem is likely internal with the bands or clutches.
How many miles on it, btw? Original transmission? Fluid clean & red?
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Thanks @TerryA@DJ RaMiN,
A long time ago my wife had a similar experience in our 84-500SL the car wouldn’t move in any gear. She was exiting the 91 Frwy and got stuck in the middle of the off-ramp.
She phoned me very upset to say the least telling me the transmission broke. Anyway after having the car towed home I discovered the problem.
Nothing wrong with the transmission. It turned out to be a deteriorated plastic ball in the throttle assembly that wouldn’t allow the throttle to open. You could floor the gas pedal and nothing happened.
Also had a similar experience in our 86-300E.
30 year old plastic parts crumble.
Check it out.
Good Luck
I have a good functioning 500e valve body that I took out when replacing with a 400e FGS body a couple years ago. Can send it your way if desired.Thanks for your input, sir!
Unfortunately, I don't have a spare VB, I'll have to look into local junkyards.
For now, I can try to remove the VB and see what's up.
Car has about 99k miles. I believe the transmission is original. Fluid looks clean as well. Do these AT's go out this early? My 190E's 722.4 is still going strong at 210k miles!

That would be great, thank you for your offer, I will let you know!I have a good functioning 500e valve body that I took out when replacing with a 400e FGS body a couple years ago. Can send it your way if desired.
Great! Thank you for all the help and info!There's almost zero replaceable parts for the valve bodies. You can get new springs & pistons for the K1 and K2 spring trains... nothing else. Otherwise you are just cleaning and inspecting for broken springs.
That diagram should be accurate. When cold and with the engine running, the level should be roughly a half-inch below MIN. Low fluid level should not cause the problem you have though...Now one thing I still don't know, is if the fluid is low or not. The "cold" level check below is not accurate, huh?
View attachment 217526View attachment 217527

Thank you, sir!That diagram should be accurate. When cold and with the engine running, the level should be roughly a half-inch below MIN. Low fluid level should not cause the problem you have though...
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I followed the DIY here and MB manual and put about 8.5 quarts after draining TC as well. One thing to point out is that I haven't driven the car in freeway speed after doing the ATF change. I mean of course I initially did the 20-25 mins to check the fluid level when hot. But nothing else after that. This Saturday was 40 mins drive in twisty mountain hwy with lots of up and down hill on a hot day!Hmmm. The dipstick can be very difficult to read, it may take repeated measurements. It's unlikely to be overfilled, but if you confirm it's at MAX when cold, it should go above MAX when warm or hot. Do you recall how many quarts you put in at the last ATF change?
The 722.3 is fully mechanical, there are no speed sensors to cause shift problems. That also means, no fault codes for the transmission.
Assuming the shifts are good without any flaring or harsh engagement, I'm still suspicious of a valve body problem. If you had a clutch or band problem I'd expect the problem to be persistent, not intermittent, but it could still be something wonky with one of the bands. I don't know the internals well enough to speculate which band, or how to try and fix it...
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I did remove the pan and replaced the filter.If you removed the pan to change the filter, and added 8.5 qts, it should be fine.
If you only drained the pan + converter (and did not remove the pan)... it may be siiiightly overfilled.
I like the level at the MAX mark with the ATF fully hot.

Thank you!Looks great! I'd still try to pick up a spare VB, and when you have time, install it to test it out (after cleaning / inspecting for broken springs inside). A large Tupperware-style plastic container works well for storage, as the VB's ooze ATF endlessly.
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Nice! Yes, this is the ball top version!Nice find! The antennas are usually repairable. You can bench test them easily. I believe the one you picked up is the "ball top" style, and the grommets are still available new for those.
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Oh I made a mistake copying the part number.Where did you get that part number? 020-997-25-47 is for a later diff.
The early 90's diff for the 034 should be 014-997-72-47 but please double-check that. No special tools required. Use Right Stuff, or the MB black sealant (Loctite 5900), for the rear cover.
Don't touch the pinion seal if it's dry... just leave it alone.

Always, always ignore any fitment information from the online dealerships. These are notoriously inaccurate. Only use the EPC to get part numbers, then plug in the part number. Supercession information from the dealers is usually valid. But the years/models shown for a part number... pretend you don't see that info.I was searching 014-997-72-47 and on classicparts.mbusa.com I clicked on "Also Purchased" and got to 020-997-25-47. And copied that part number by mistake. What's strange is that website claims that the later part also works for my car!![]()
Any hook tool can be used to pull the clips out - doesn't need to be the special MB tool, but if it's cheap, go for it! To press the new seals in, use any flat round thingy that matches the outer diameter and gently press / tap the new seal in place. Just make sure it's 100% flat / parallel. I forget how I did this but I don't have the special tool for the seals.As far as special tools, I was reading this manual and it says in order to remove the connecting flanges, I'll need a hook tool to remove the circlip and some kinda alignment tool is needed to press the new seal in?

Yes sir! You're 100% right!Always, always ignore any fitment information from the online dealerships. These are notoriously inaccurate. Only use the EPC to get part numbers, then plug in the part number. Supercession information from the dealers is usually valid. But the years/models shown for a part number... pretend you don't see that info.
Any hook tool can be used to pull the clips out - doesn't need to be the special MB tool, but if it's cheap, go for it! To press the new seals in, use any flat round thingy that matches the outer diameter and gently press / tap the new seal in place. Just make sure it's 100% flat / parallel. I forget how I did this but I don't have the special tool for the seals.
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