• Hi Guest !

    Welcome to the 500Eboard forum.

    Since its founding in late 2008, 500Eboard has become the leading resource on the Internet for all things related to the Mercedes-Benz 500E and E500. In recent years, we have also expanded to include the 400E and E420 models, which are directly related to the 500E/E500.

    We invite you to browse and take advantage of the information and resources here on the site. If you find helpful information, please register for full membership, and you'll find even more resources available. Feel free to ask questions, and make liberal use of the "Search" function to find answers.

    We hope you will become an active contributor to the community!

    Sincerely,
    500Eboard Management

Slowly loses 3rd & 4th gear after driving

Raphial

Member
Member
Hey guys, this is my first post on here. It's been awhile since I've used forums, but I'm hoping I can get some help here. I have a small shop, and have been periodically working on this gorgeous 95 E420 I have. When I first got the car, 3rd and 4th gear were near non-existent. Could never get them to engage. I've replaced the kickdown switch behind the pedal, I've properly adjusted the kickdown cable on the throttle, I've drained the trans and torque converter, replaced the filter and K1 spring assembly, then added new Dexron 3 fluid. Now the car runs a ton better, but I still lose 3rd and 4th gear after about 15-20 minutes of driving, and then I only have 1st and 2nd gear. It acts like it loses fluid pressure, or is the wrong fluid (It has the right capacity of fluid).

I'm at a loss right now, and have set it aside for our other projects. Any help or ideas would be appreciated. Thanks!

IMG_20210205_164502.jpg
 
I assume you have confirmed the fluid level is at MAX on the dipstick, when the transmission is fully hot (80°C ATF temp), after driving 20-30 mins at freeway speeds. After draining the pan AND converter, and replacing the filter, it normally takes 8.0-8.5 quarts to fully refill.

If fluid level is correct, I have no idea what the specific failure might be. Other than trying a different valve body for grins, I think the typical recommendation is to replace the transmission with either a known-good used one, or rebuilt. @JC220 might have some ideas but most people have not done internal transmission repairs.

:wormhole:
 
Hey guys, this is my first post on here. It's been awhile since I've used forums, but I'm hoping I can get some help here. I have a small shop, and have been periodically working on this gorgeous 95 E420 I have. When I first got the car, 3rd and 4th gear were near non-existent. Could never get them to engage. I've replaced the kickdown switch behind the pedal, I've properly adjusted the kickdown cable on the throttle, I've drained the trans and torque converter, replaced the filter and K1 spring assembly, then added new Dexron 3 fluid. Now the car runs a ton better, but I still lose 3rd and 4th gear after about 15-20 minutes of driving, and then I only have 1st and 2nd gear. It acts like it loses fluid pressure, or is the wrong fluid (It has the right capacity of fluid).

I'm at a loss right now, and have set it aside for our other projects. Any help or ideas would be appreciated. Thanks!

View attachment 129752
Welcome!

So you did see an improvement post trans service. Was the old ATF black / dirty? Do you still have the old filter laying around? Perhaps cut it open with tin snips and inspect the filter media for metal or sludge.

You probably have nothing to lose by performing another fluid and filter change given the initial change you did appeared to help.

Unfortunately it could be losing pressure and nearing rebuild stage.... 4th gear is one of the more demanding ones in hydraulic terms.

You didn't mention the vacuum modulator, was it changed or adjusted? I would suggest also buying a trans pressure test gauge set from fleabay or harbour fart and a 722.3 workshop manual for test specs. (I posted the 722.3 workshop manuals on there before and the How-To section has lots of 722.3 goodness)

So first do another fluid change cheap correct spec fluid will do just fine. And whilst in there check the vacuum modulator pressure / adjustment. There is a newer version on these cars identifiable with a black cap IIRC. If in doubt, replace it and set pressures correctly.

At the risk of the Emperor's rath, I might also suggest a tube of Dr Tranny Instant shudder fix when doing the 2nd fluid change now, you have nothing to lose. After that I'd probably swap in a known good valve body as Gixer said before pulling the whole unit.
 
Last edited:

Who has viewed this thread (Total: 1) View details

Who has watched this thread (Total: 1) View details

Back
Top