motor mounts
 

how bad of a job is changing a right engine mount on a 350SDL? The shop manual has every model and picture imaginable except WHAT IS ON THE CAR!
Symptoms are a bad vibration in fwd none in rev and it disappears under load.

Sounds like you're thinking of doing just one side.

I would do both AND the transmission mount as well - three in all.

I love to DIY and this is a doable home task, but a pain.

It's just my opinion, but the shop labor to replace these parts isn't all that much and if you're the type that wonders if the part REALLY got changed, you can easily verify this happened.

I illustrated the job on my 1983 300SD. While the mounts for the 350SDL are different (left and right also differ), conceptually the job should be similar, with access maybe a little tighter on the 350.

Be careful to align the mount when replacing the bottom bolts or you risk cross-threading. I illustrate one version of a workable procedure.

You may want to check with 'gsxr', 'Jim SMith', 'engatwork' or 'Rick Miley' on the diesel section of this board - to name just four big body diesel experts.

Definitely replace both engine mounts, if one is torn or otherwise noticeably bad, the other one is bad as well. The tranny mount is a simple job. The engine mounts aren't overly difficult, but as Thomaspin stated you do have to use caution when starting the bolts or risk crossthreading.

Be sure to loosen the fan shroud to allow a little more lift when you start to jack up the engine. All of the hoses should have enough flex to leave them in place during the procedure.