Possible mount failure?

[PumaRun12]

So I will try to describe this the best I can.

I think I might need new motor/transmission mounts.
I have a 99 c230K.

When the engine is cold, I start the car it starts up a little rough - probably just because everything's kicking in at once, and then as usual it settles down rather quick. - so that seems normal. My problem is though, one these cold starts if I leave my car in 'P' or "N' - it is fine; but if I put it in 'D' and sit on the brake (not moving) it shakes vigorously (putting it in 'R', it only shakes a little). After driving the car up to operating temp, the shaking completely goes away when stopped and still in D.

So would bad motor mounts only affect this? if not, what else do you think it could be??

Thanks in advance

[jc1kz]

Here is a video from you tube to see if it is the motor mounts...

Mercedes engine mount testing - YouTube

Mercedes engine mount testing - YouTube

[PumaRun12]

alright, I tested that this morning, and there was slight movement, nothing really dramatic.

So I guess I can change them, I just didn't understand why it only vibrates when its cold, no other time.

My car is due for a fuel filter and a complete oil change - possibly doing a coolant flush too, in the next few days, maybe that will help?

[glenmore]

How many miles on this set of mounts? Were they OEM or some other brand?

I would think the vibration from bad motor mounts is continuous regardless of engine hot or cold. Not noticeable at speed but most obvious you are at a stop. For me it was most noticeable when doing slow speed maneuvers like parallel parking.

[PumaRun12]

I am not sure if they are OEM or what...

The car has 150k on it, and it was serviced fully by a MB dealer until 125k...

And that is what I was thinking, so I couldn't understand why it only happened when cold. Would the same go for the Tranny Mount too?

[glenmore]

Only guessing, but in 125K, mounts were probably done once at the dealer with a hi-quality OEM part.

You can just take a look at the tranny mount to see if it is broken or really smooshed. It is readily visible.

[oberoi]

Tranny mount can look good and still be crap - Replace anyway along with motor mounts

Oberoi

[Triggerhappy]

The motor mounts probably need to be replaced at 150k (if they weren't replaced by Mercedes at 100k) but this does not sound like a motor mount problem.