Vibration under load

[Rolo]

Just when everything is starting to get good, my 6.9 has developed a vibration under power.  Most noticeable at lower speeds like climbing a steep hill at 40 mph.  A gentle shake, but you can definitely feel.  About 2,000 RPM with 3/4 throttle brings it on.  Not noticeable off the throttle or at freeway speeds.  Gets a little worse with more revs.

Car has new flex discs and thanks to the this Forum, a well aligned propeller shaft.

Any ideas?  Thanks.

[Jan S]

Did you replace the drive shaft center bearing and the rubber mount at the same time as the flex discs?

I had the same problem .... due to shot rubber mount for the center bearing.

[daantjie]

Also check diff mount and transmission mount.  If suspect replace with Benz parts only.  They are both relatively easy replacements and can cause the vibration you are describing.

[Rolo]

Bearing done, mounts, I can't remember.  Will check all.

This Forum is great!

[Rolo]

More troubleshooting to report.

Vibration is much more evident while turning under power.  Up hill turns bring out the worst.

Any additional tips?  Thanks