Changing Transmission mount - PeachParts Mercedes-Benz Forum

jmcgill · #1 09-08-2009, 07:05 PM

I had my 300D at the garage today getting a checkup and they told me that the motor mounts were crushed and the transmission mount needed to be changed in the very near future.

I didn't have the time (or the money) to have them do it today, and I don't think I'm going to have the $400+ to have the garage do all the mounts.

My question is whether there is a primer out there on how to change the tranny mount?

Thanks for any help.

Joe

ImBroke · #2 09-08-2009, 07:39 PM

Nothing difficult. Make sure you support the trans when you remove the crossmember. IIRC, crossmember to frame (4) bolts are 17mm, then there's two 13mm that hold the crossmember to the mount, and one 13mm that holds the mount to the trans. That one could be a 15 also.. it's been a while.

jkubica · #3 09-08-2009, 08:12 PM

Quote:

Originally Posted by jmcgill

I had my 300D at the garage today getting a checkup and they told me that the motor mounts were crushed and the transmission mount needed to be changed in the very near future.

I didn't have the time (or the money) to have them do it today, and I don't think I'm going to have the $400+ to have the garage do all the mounts.

My question is whether there is a primer out there on how to change the tranny mount?

Thanks for any help.

Joe

Hi
As Imbroke above said the trans mount is a strightforward job that took me about 20 minutes and I'm a slow worker. A piece of wood on the floor jack will prevent bending something up.

The motor mounts are more involved but still a DIY project. There are a number of good threads covering procedure. When folks have problems its usually stripping the allen head motor mount bolts because they didn't take time to clean everything up so the hex wrench fits in right.

Less than $100 for all the mounts depending where you buy.

Joseph

i

MBeige · #4 09-08-2009, 09:10 PM

The top nut is 19mm.

Make sure you get the square type of yours is automatic. I returned the wrong mount when I got the one with an oval tube. The correct one was square and was beefier than the one with an oval tube between the braces. My guess is that this type is for manual transmission equipped models since it was actually softer than the correct type.

Correct type on the right, mount w/ oval tube on the left:

The original mount was actually stronger than the Febi Bilstein unit I got w/ an oval tube so I sent it back. Waiting for confirmation so I can go ahead and get the correct type.

jmcgill · #5 09-09-2009, 06:23 AM

I was doing some reading in the Factory service manual last night, and that one with the oval in it was one they used in the cars made before 1981 or so. In the later cars they went to the one on the right.

I should be able to do the Tranny mount pretty easily. I will buy some engine mounts too.

I'm looking for German parts?

MB300Dave · #6 09-09-2013, 02:12 PM

Nice Pix MBeige! Since you're at it, make sure your oil cooler line are OK as well.

Someone buggered up my hex on my L MM, not funny!

So I know what you mean jkubica!

D

MBeige · #7 09-09-2013, 03:14 PM

Oil lines were done years ago, before this job, but thanks!

Diesel911 · #8 09-09-2013, 09:47 PM

The extremely costly Motor Mounts from the Mercedes Dealer are actually made by Phoenix (made it Turkey).

Lemförder/Lemfoerder/Lemforder grinds off the Mercedes Star on the Motor Mount but leaves the Phoenix logo on it and the MB Part Number and if you shop around they are in the $24-$30 each range.
Lemförder/Lemfoerder/Lemforder also makes a Transmission Mount but it is harder to find an internet site that sells them.