Hello

my car is a 182000 mile 2002 C32 amg, it’s that bright yellow one with the black roof, lots of pics on the internet so you may have seen it.

So ever since I bought it the gearbox seems very odd compared to other 722.6s I’ve driven in.

im planning on doing a full refurbishment of the underside, suspension, engine and transmission this winter as it’s starting to feel it’s age and mileage.

Im having a few weird moments with the transmission and I’d like to hear some opinions so when I come to do the refurbishment I have a better idea what I might be looking out for/replacing.

The car has a 65mm pulley and an Ecu tune btw. I’ve reset the transmission adaptions very frequently too btw.

Issue 1 when I drive up the small hill away from my house, cold engine and trans the torque converter lockup just keeps coming on and off as I go up the hill at around 20mph. You can see the RPM gauge going up and down every second and the engine note changes, kinda goes brumbroombruumbroom, you get the picture. This issue goes away when the gearbox is hot.

Issue 2 when moderately accelerating, 1/3-2/5 pedal travel sort of thing sometimes the car will feel like it does a gearshift, revs are rising then they go back down like it’s changed gear then they go back to we’re they were a second ago, it’s like it does a gearshift without changing gear. I think this is the torque converter lockup turning on and off and then back on then it will perform an actual gearshift.

Issue 3 When going from low rpm low load to putting your foot down, for example when coming off a roundabout you are in 3rd just cruising around and you take the exit and put your foot down half way. The trans will shift from 3rd to 2nd and then lockup the torque converter but it feels like it’s really struggling to lock it up, you feel it begin to engage it and the engine note sounds like a plane coming out of the sky, pitch slowly dropping as the lockup increases. I’d say this event take about 1.5 seconds to happen but when it’s locked up it’s fine.

The trans works flawlessly when at WOT. The previous owner replaced the solenoid for the lockup and the current gearbox fluid is within the service intervals.

I guess I’m having an issue with the solenoid or part of the valve body, damper valve etc? Or possibly the clutch disks in the torque converter are worn out?

any input would be helpful

thanks
Aidan

 

I´ve changed the lockup-solenoid twice, first time for harsh lockups when cold and second time for undecisive lockups.
It seems to be very sensitive for dirt and residues.
Check out my thread regarding this if you haven´t:
https://mbworld.org/forums/c32-amg-c...em-solved.html

 

Ahh I guess when the last indie installed a new solenoid he didn’t do such a great job then! Thanks for the advice.

 

I’m not so sure a new solenoid is the solution. Some people feel otherwise; I believe there is more to it. Simply replacing the solenoid almost seems to good to be true. I acquired my ‘02 w/ around 66k a few yrs back. It has been well maintained in the past. The original owner replaced the radiator and flushed the trans fluid around 42k. This list goes on.. I love the car, but this issue is hard to overlook at times. Especially in heavy traffic situations. I’m well versed on the 722.6 trans after owning a few 210 and 208 55’s. They act completely different to one another.

Many people post a positive review the same day a new part is installed. I have come to realize the following morning can be a complete letdown. A new solenoid under these circumstances most likely requires 100-200 miles. Many mixed reviews which is my reasoning for not replacing this part with the updated one:

https://mbworld.org/forums/c32-amg-c...em-solved.html

 

I Think when I have the gearbox out I may just swap out the 182000 mile valve body for a reconditioned unit, new conductor plate and solenoids. Replace the clutch packs and o rings on the mechanical side of the gearbox too.
Then have the TCU adaptions reset. That’s probably why it takes a few miles for people to notice a difference, the computer has to work out all the values that it constantly adapts.

 

I’m leaning towards the adaption reset. I cannot justify the work on my car w/ a potential no result outcome.

GL.

 

Please keep us updated. I too have been considering a full valve body/solenoid/conductor plate swap sine I have ~199,500 miles And the only flaw is odd behaviors like you described above. Rather than chase my tail with this part or that, I’d replace the whole thing and reset the values to hopefully make the trans function as new.

the car is awesome, but I feel like the trans if often confused like I think you are experiencing.

 

Everyone experiences this issue on a C32. A big factor is how you drive it, if you drive sluggish the trans will adapt. I’m surrounded by traffic lights which definitely spices things up.

I doubt the original parts are the culprit. I put my money on the software which controls it. Regardless the car is “awesome”.