b4 motor mounts , how to tell if marginally bad

I have 95 K on my B4 TDI passat. I'm replacing r-rear and front motor mounts. I can't say that they are bad, as they seem to be big hunks of rubber. But I suspect that the rubber only has so many "vibes" before it looses its resistance to swing.

I needed to replace inner r-CV boot, so it just seemed like the time to do the mount as looks very difficult to do with 1/2 shaft in place.

I have them out, they seem to be solid, what fails.

the front mount is easy. I think the rear ones are a different game...far more involved. I've replaced just the front and found quite an improvement. The rubber hardens and compresses over time which transfers more NVH into the car.

If your stick vibrates, replacing the front mount will probably solve this. Also, as the front mount compresses it becomes more difficult to remove your oil filter. Removing the front mount isn't difficult but you have to remove the starter bolts to get the bracket out. Mine was obviously compressed quite a bit since the round swiss-cheese holes had become very oval-shaped. As the rear mount ages and compresses, your exhaust system will begin to sag. Mine got to the point that my after-cat flex pipe banged on the exhaust tunnel cross brace. The tranny mount is hydraulic. The most obvious sign of failure (besides vibrations or a clunk) is the appearance of black tar-like substance oozing from the top.

As long as the bolts aren't siezed the rear right mount is easy. Remove the lower subframe vibration dampener (AKA. big steel brick) to make access easier. Replacement of the tranny mount is the most difficult because the power steering lines are in the way. I used ratchet wrenches with swivel heads to remove the lower bolts. Without this, you could spend 45 minutes just trying to loosten the bolts. It's a PITA and there's no room to work, especially if you have big hands. Before you start, make sure you have a few flex joints and various extension rods for your ratchet - you'll need them to remove the top bolts. Note that you can't remove the tranny mount bracket completely since one bolt won't come out. You can however wiggle things around enough to get the mount out of the bracket. Finally, make sure that you get a hydraulic tranny mount. The first one I got from an aftermarket supplier claimed to be an improved design but turned out to be a solid rubber VR6 tranny mount. The noise and vibration inside the cabin was unbearable. On the plus side, the second replacement only took me 45 minutes /images/graemlins/crazy.gif

Rick

ps. you don't need to remove the half-shafts to replace the mounts. I'm not sure it would help anything but if they are shot it can't hurt either.

maybe you have a different car, I have a 96 TDI. The front mount comes out without any starter drop. I just jacked up engine, then out 5 minutes or so. I just did remove the 10mm hose clamp to move a rigid line. I think if you have the oil filter out, it would come out that side easier.

The rear is easier...... after you have the half shaft out. I was R/R-ing the inner CV boot, so the mount was right there, very acccessable.
Again just jack up the rear of the engine and remove three simple bolts + a exhaust sniffer line from the manifold.

Now after all is said an done, I can't say that it is better, maybe a tad. But it was my plan to do the mounts hoping for a dramatic improvement. My 95 passat GLX has hydrolic mounts, while the TDI is Cheese rubber.

Ahhh ... you did it the easy way /images/graemlins/wink.gif. I was concerned about overstressing / breaking something I couldn't see while jacking the engine up far enough to get the mount out so I removed the bracket from the car to change the front mount. Having the filter out would definately help prevent skinned knuckles ...

Changing my front mount made a big difference in vibration. The rear mount lifted a sagging exhaust but otherwise didn't change much. I guess it depends as much on luck as anything else. Some people seem to go forever on the original mounts without ever having a problem while others report having to change them after 100k miles. I wish my car fit into the first category ...

Rick

i keep expecting to need to change them, but i've got 153k on the original mounts and the shift knob doesn't move at all, and the rear seems perfectly good too.

*shrug*

hmm--276,000 on mine--no stick shake--and no drooopy exhaust--strange,isnt it????? and still goes like scat-----

Guys,

I replaced mine on a "miles" basis. After I removed my old mounts they appeared to be fine. They are simply a chunk of rubber with holes in it. My new mounts did not really change anything, yes gotta be better and firmer but it's a fine line.
I have 95 K on the car and I will continue to change out components. Next are the struts, mine seem fine, but I work in 50 K increments.

I've seen what it takes to remove the only mount nobody has mentionned so far: the rear left one.

It is the most difficult to get.

It took 1TDIGUY and Boucanier 3 hours to take the old one out and put the new one in.

In a near future I'll change the front mount too.

Thanks for the advice given earlier! /images/graemlins/wink.gif

The rear left mount is the transmission mount - it is a PITA to remove (the first time, anyway /images/graemlins/crazy.gif).

Rick

[ QUOTE ]
The rear left mount is the transmission mount - it is a PITA to remove (the first time, anyway /images/graemlins/crazy.gif).

Rick

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Oh, that's how it's called, sorry, I thought it was another motor mount. /images/graemlins/rolleyes.gif

Thanks for the rectification! /images/graemlins/grin.gif