FRANTOMAS

Hello Everybody,

I have problem with my automatic transmission during constant and smooth drive. Usually when car has 1500 RPM and constant speed on 4th or 5th gear ( it does not matter) on highway or on narrow road it starts to rev up and down from 1400-1600 RPM and car jerks a little bit. It repeats again and again until I slow down or speed up. It is similar feeling like to be on tho boat on waves :-) It does not seem that car needs to change the gear but car push a bit. This issue also happens when a put my hand off the throttle and car is slowing, it jerks a bit. AT itself shifts up and down ok.



If anybody has experienced something similar or have any advice I would be grateful.

Frank

oldsinner111

Mine does it too,only when cold.Check fluids first,then check for leaks.I've been told,if I replace my conductor plate it will stop it.

FRANTOMAS

Thank you for you reply.

I have new fluid and Torque Convertor was flushed regulary... I did some research yesterday... It is probably something with solenoids, or conductor plate as you said or Torque Convertor Clutch. I am trying to find somebody who had the same problem and went through...

My car does exactly the same thing like this 7226 in different Mercedes model, it does not matter about oil temperature:

oldsinner111

from what i heard about flushing,is its a bad thing to do.removing pan and replacing filter is the best way.Also make sure the fluid is non conductive.Don't go to these lube express,or wal mart.They will ruin your car.

mirimar69

I have just completed removing conductor plate and while I did not have your particular problem I would also agree with others its your conductor plate, perhaps the speed sensor situated on the conductor plate. Mine was cracked through the insulation. You can test the solenoid valves by hooking up to 12v battery. If they click they r working. $200 aussie dollars for a conductor plate. $155 for fluid. $50 bucks for filter kit and $100 torque wrench. $500 dollars in front. Drained overnight. took my time over the weekend. Watch mercedessource on you tube. He has 5 episodes on how to. Pay close attention to the cleanliness of your work and the torque settings (8.1 Newton metres/ 72ftlbs ...allow for individual calibration) particularly for the metal on metal aluminium valve body . I did not bother with the torque converter drainage as I have decided to let the filter do the work for the next 5000kms and then drain again but thats just me....she purrs now. I hear the gear change but I feel nothing ...even in step-down. My fluid was black/green and sludge but no discernible metal fragments.

Alternativel it could be a 4 -5 shift sleeve problem..ie worn and would require the sonnax kit for the 722.6. Tough one to decide which way to go. Assuming you are mechanically adept to take it on..you may just have to open her up and remove valve body conductor plate assembly(one complete unit) and inspect the conductor plate first. sonnax instructions http://www.sonnax.com/parts/2317#tabs1-instructions if you decide to install kit while you have it out. Caution lots o springs behind the valve cover plate...open carefully...hope this helps