Ok ,first drive since I bought it in Feb 09, (long story) Seems to run well but trans shifts kind of strange compared to my old Focus. I drove to the local Dino peddler and filled up. By the way there was a strong suction when I removed the fuel cap. Anyway got in the E way and run her up to crusing speed and noticed a vibration that seemed to start at 58 mph and increased as i sped up. It is smoothe from 0 to 58mph. I have read some other posts on vibrations but could not find anything on my model 300SD. I did replace the engine and did mark the drive shaft when I disconnected it. The flex disk looked good but i did not check the rear. I should mention that it does have different rims and tires, wich look in good order. I am going to have the balance checked next week. anything jump out that i should check first?

Does the vibration come through the steering wheel or your seat? Is it just a vibration or is there a thumping as well?

Sixto
87 300D

It is hard to tell, it was a short drive and I did not want to push it. I will run it again Monday. Today I checked all the lug nuts to make shure they were tight and i noticed the driver side rear wheel had some play in the outer control arm bushing. I don't recall any thumping but it seemed like the whole car was shaking.

You need to determine if the vibration is at driveshaft or wheel speed. Driveshaft speed is about 3 times as fast as wheel speed.

That said, a couple of facts about vibrations:

High speed vibrations are, in the vast majority of cases, wheel/tire related. Especially in a car that has sat on it's tires in one spot for a year and a half.

Vibrations are one of the most difficult things to troubleshoot over the internet.



Do you have a buddy with a known smooth set of wheels & tires on a similar car? If so, you could simply bolt them on and go for a drive. It would be a quick way to determine if the vibration is wheel/tire related.

Hope this helps.

Thank's , I have a set of the Bundt wheels but tires are quite dry rotted. These were on it when I drove it home from Pittsburg and I don't recall any noticable vibrations then, but the loud knock took most of my attention!