300e vibrates when accelerating
 

my 86 300e with 157000 miles runs great but has started vibrating under load acc, motor mounts were changed, trans, rubber drive joints aren't very old, new tires, everything under the car is tight, also just changed cam and rockers, 15000 on valve job, just can't figure whats vibrating, any ideas, thanks

you might want to think about haveing the trans checked it could be slipping and that is called a shudder in transmission terms if you put the gas on the floor from a dead stop and the enging starts to free wheel than its a go on a rebuild the band servo is not holding, the seals in it get hard from the heat cycles of 150,000 miles and it does not have the ability to hold the drum from turning when it is susposed to hold it still hence the shudder or vibration - jz

no it doesn't freewheel, just put lucas trans. stuff in it

Just had a similar situation...
 

One of my spark plug wires was loose...You may also want to check other ignition components.

no plugs are good new wires, it does not vibrate till around 50, can't feel accelerating until then, even with it on jacks

I assume the E-class has a two-piece driveshaft like the S-class. The center bearing and u-joint can certainly cause vibration, even if the front and rear flex-couplings are good.

DG

silver, it's possible one or more tires are out of balance or have slipped belts. Swap wheels and see if the vibration moves from front to back.

new tires and rotated, I am thinking center bearing also, I just had my neck fused so it will be a few weeks till I can get near it

I'd also vote for the center bearing or support as you have pretty much eliminated the normal suspects. My recent parts car acquisition had a vibration going forward and a huge amount of noise and vibration in reverse. Was told the "diff fluid needed changing":confused:. I didn't care as I wanted the 5 spd bits. Got it home, drove it in reverse, helper said noise was from the middle. The center bearing was fine, but its rubber support was almost non-existent. Its not a difficult job, just a whole lot of R+R to get the shaft out.

I had a similar problem with vibration when accelerating around 1750-2000 rpm, luckily it was just the intercooler pipe

I know i have changed flex joints on this once when I got it and my old 83' 300d