slight juddering

[GH421]

Hi!

my w221 is juddering slightly when accelerating at certain speeds sometimes. This is between 25-30mph and 55-65mph. It feels like a wheel bearing but the judder feels like from under the car and is worse when there's a full load.

Anyone had this problem?

 

[Telebass]

Don't know if the parts are similar to some w211 models, but there is a thing with cross-contamination of coolant and ATF due to corrosion on the combined radiator. Either that, or the ATF is very old and needs changing, maybe?

 

[4life211]

or the torque converter it is on the way up .

 

[Tim203]

If you've done the fluid change and it's still doing it sounds like the lock up clutch is beginning to slip. This was the case on my W203 and it only got worse. An independent with Star can prevent the lockup clutch working thus proving it one way or the other.
I stuck some BG conditioner in and it fixed it. A mechanic friend swears by a couple tubes of Dr. Tranny on Range Rovers with the same issue.