W124 drivetrain vibration/rumble - PeachParts Mercedes-Benz Forum

2.5Turbo · #1 01-03-2009, 08:41 PM

What's next?!

My 124 has developed another problem...now something in the drivetrain is vibrating above 40mph. At first I thought out of balance tire, but I noticed the intensity drops dramatically when cruising at part throttle, and increases on acceleration and coasting. The frequency of the vibration coincides with the speed of the car, not with the RPM, so it looks like it's driveshaft/diff related. I'm guessing flex discs are a good place to start looking...sure hope my driveshaft didn't somehow get out of balance.

I'm sort of wondering if it's related to getting stuck in the snow a week and a half ago; it didn't do it before then and today was the first time I had it on the freeway since then. Did a lot of rocking and wheel spinning trying to get the car out.

This does give me the opportunity to use my new mechanic's tools, jack and jackstands I got for xmas...guess my car noticed I finally had my own tools and decided to give me something to use them on

Bio300TDTdriver · #2 01-03-2009, 08:52 PM

I would pull each tire and make sure you haven't accumulated a bunch of sand or mud inside the wheel. Then look at them and see if there are any clean spots where you lost a weight. If it happened after our recent snow and you got stuck, I believe it is related.

Then again it could be the flex discs, as they probably take some abuse when going back and forth from reverse to forward to get unstuck.

2.5Turbo · #3 01-06-2009, 01:04 PM

Lifted up the car yesterday and took a look. Wheels were fine, no missing weights that I could tell. After checking the wheels, I looked up at the diff and saw a hole in the rear flex disc where a bolt was supposed to be

. Needless to say the car is sidelined until the new one arrives.