'96 C280 Driveline Vibration when Cold
 

Hello, all,

I have a '96 C280 (W202) with 112K miles which is experiencing a mild driveline vibration from 60-70 mph when cold. After driving about 3 miles, the amplitude of the vibration decreases significantly, but is still perceptible.

Thus far, I have balanced tires & wheels, replaced brake discs, and replaced both front and rear flex discs. Transmission fluid level is verified as normal.

I would be grateful if someone could give me some insight on a possible cause and solution.

Many thanks,
Edward

What make of tires?
Sure sounds like your tires are flat-spotting. ;)

Nope, four new BFG's had zero effect.

I'm wondering about the driveshaft, CV joints, things like that. I'm running out of things to replace.

Could be your engine mounts ,they are hydruallic and lose pressure over time .
As your engine heats up the pressure in the mounts will increase slightly ,hence the change in the vibration pattern.
Geo.:)

My personal experience is that engine mounts and front shocks work as a team/system in controlling vibrations/frequencies - but I don't know if a professional tech would agree.

Concerning a cold engine/driveline, I always try to put on five slow miles on a cold engine and drivetrain before upping the revs or speed.

Thanks, I'll investigate engine mounts/shocks as I doubt that these have ever been replaced.

--Lee