mis3

My 2004 CLK320 is now 10 years old and it has over 180k miles. I am thinking it's probably time to change the engine mounts and transmission mount. Should I wait for symptoms or just change them?

I checked Autohausaz and these are what I found:
Engine Mount. Lemfoerder $89.
Trans Mount:. Corteco $32 Or Uro for $14.

Do you guys have experience in these parts? Also, do I need any other parts to replace these mounts? Should engine mounts and transmission mount be changed at the same time?

Glyn M Ruck

I would wait for noise or vibration symptoms. Mount life is hugely effected by the way the vehicle is driven. If you are a gentle driver mounts can go a very long way. The rear engine or transmission mount is usually first to go. Usually a clonk or vibration from the transmission tunnel.

I believe in changing all 3 mounts at the same time otherwise you just stress the new mount.

mis3

What noise or vibration should I be looking for?

For instance, when my car is sitting idle at a red light, I can feel some vibrations. The vibrations would stop if I put my car in neutral or park. Is this a symptoms of worn engine mounts?

I understand that these mounts are consumable items, ie: like engine oil and oil filters, they are worn down over the years. I am thinking after 10 years and 180k miles, they must be somewhat worn down.

Rudeney

Yep, vibration at idle, or stopped and in reverse are symptoms. Especially in cold weather. the two engine mounts are fluid-filled and they tend to leak and collapse. The rear mount is just rubber, but it also weakens and "drops" over time. If you can deal with the vibration, then don;t worry about it - it's not a safety or performance issue.

mis3

Yes, when I stopped the car, it will have slight vibrations at "D”. The vibrations will be gone if I shift into "N" or "P".

By rear mount, are you referring to the transmission mount?
As for 2 engine mounts, are the 2 mounts identical?

How much labour, in hours, does it take to replace these mounts?

I checked Autohausaz and Parts.com, their prices are similar. In Parts.com site, they said they carry genuine MB parts, does this mean that their parts have MB logo and MB packaging?

Glyn M Ruck

In Benz speak you have 3 engine mounts. We only talk about the transmission mount for clarity.

The front engine mounts are identical & MUST be replaced in pairs.

There is a procedure for replacement on M272 & M273 in the Wiki. The same applies to the M112 although the mount P/N's are different.

I have no idea how many hours Benz books this at. Maybe Rudeney can help. With a proper engine lifting device it's not a major job.

As to whether the vibration worries you ~ that is personal. I must say cars feel like new with new mounts. Also when the rear mount goes soft you sometimes get a clonk out of the transmission tunnel when turning over a diagonal depression.

mis3

I will definitely go for it for the new car feel. Hope the labour is not too expensive.

I also read that some people were having more vibrations after the change. Maybe the root cause was inadequate parts. I see engine mounts from Febi, Lemboerder and Meyle in different online stores and they all claimed to be OEM.

This is why I ask about parts.com, over the years i have developed confidence in MB parts from the dealerships. I think I should go with OE for these mounts.

Rudeney

For both front mounts, ASRA shows 41 work units (5 minutes each) so about 3.5 hours. Now, this is doing it "the official way" which involves removing the MAF sensor, engine fuel line, and exhaust system in order to lift the engine. In practice, if you are veyr careful, you should be able to lift the engine just enough to remove the mounts without all of that work. The rear (or transmission) mount is 13 work units (about an hour).

mis3

I will suggest this (not removing everything) to my indie. Will be AC module in the way?

I found 2 online stores as suggested by some members here, parts.com and oediscountparts.com, their prices are similar. Not sure if they carry the same mounts.

My friend suggested performace engine mounts from ECS Tuning but I'm concerned about fitment and quality.

Glyn M Ruck

Performance mounts will transfer more vibration into the car. Only use proper silicone fluid filled OE mounts. You are not building a race car where HVH does not matter.

mis3

I observed the vibrations when I drove today.

When the car was cold, I could definitely feel the vibrations in Drive. Then I shifted to Neural, the vibrations were gone.

When the car was fully warmed up, the vibrations were much reduced. There was no much difference between Drive and Neutral.

I did my research and the forum members here seem to prefer parts.com and oediscountparts.com. I would probably order from oediscountparts, hope they have MB OE parts as claimed.

Rudeney

I know parts.com are genuine MBZ parts as they ship from a dealer network. oediscountparts.com appears to be a dealer in Asheville, NC, so I would assume they are also selling genuine MBZ parts.

mis3

I finally went to a reputable MB indie yesterday and replaced the 3 mounts. They told me it actually took a bit longer than the quote of 3 hours. They did not have to touch the alternator but had to disconnect the exhaust.

I checked the vibrations right after I started the car this morning (not too cold today, 34F). I shifted between "N" and "D" and I could not feel the difference in vibrations. So, definite improvment here!

I bought the OE parts from an online store and with labor, the total cost came up to $500. If this was done in the dealership, the same work would cost $1,245. they quoted me 4.5 hrs of labor.

BTW. These mounts came with MB packaging with MB part numbers engraved on the parts.

mis3

Just a follow up, it was an excellent decision to change the mounts. The car drives a lot better after the change.

Main improvement:. When the outside temp is -5F and my car is cold, I no longer feel the vibrations at "D".