Help with tranny mounts and motor mounts

Hello all,

The '04 360 coupe with 25,000 miles is making a slight jittery, bumpy sensation from the rear when I reverse. Not consistent. Seems worse when car is fully warmed up. At first I thought it was the tires hitting the wheel well when the steering wheel is turned to one extreme or the other but it seems to happen even when steering wheel is in the middle.

The car had new motor mounts 182142 and gearbox mount (Ferrari) 186698 in Sept. '10 at 11,000 miles.

Any suggestions?

The car will go to the dealer in Sept/Oct for its annual.

Thanking you all in advance for your expert help.

Tom

Yours,

Tom

 

Could we try this again?

OH....That's right...I mean Bump,,,

 

Not sure what to tell you. If it needs them replaced, well, it needs them replaced. I just did all of mine with the clutch and belt service. FerrariSteve looked at them and could tell right away that they were failing.

 

Thank you.

Does it seem soon??

Check wheel alignment??

Drive slower?? (LOL!!)

Could it be something else??

 

Sounds more like a chattering diff. Change the oil and put some posi additive in it. Your description exactly matches the symptoms I get backing one out of the shop. For some reason it is more noticeable in slow maneuvering in reverse.

 

FWIW, I was thinking the exact same thing the moment I read the first post.

 

Yep, sounds like diff. If it's an F1 car could it be clutch? And why would the (ANY road driven) car need new engine and tranny mounts at 11k miles??

 

I believe his car is a 3 pedal.

No idea why it needed mounts at 11k either. (possibly a bad set and just did the work to make it right?)

 

Yes...It is a three pedal. Sorry should have mentioned that.

Thank you all for the valuable information.

I just need to be able to sound a little intelligent when talking to the service guy!!!

 

I think your subject line is misleading. This isn't motor mounts. You would get rough shifts at high RPMs, not at idle, if it were the mounts.

 

Because they were garbage? Even the new ones are just good but a long way from great.

1st generation mounts were junk and even the 2nd generation trans mount was junk.

 

When the mounts go bad one symptom is excessive vibration at idle.

 

LOL! There must be aftermarket improvements, no? There are about 5 different types for the 911 I know of!

 

No

 

+1. the steering wheel on mine would vibrate excessively under my fingers prior to changeout.

Interestingly, the last monkey that installed the updated design on mine did it incorrectly. The old design just bolts down. The new design uses a spacer under the central part of the mount on the bolt. Last mechanic used the new style of mount but installed it as an old mount, essentially crushing it excessively and leading to premature failure. Even though they may look like newer style.. beware of prior installation error.

 

OOPS.

 

I can't believe there is no aftermarket, at least stiffer mounts for the CS? We had everything from stock rubber, improved (stiffer) rubber, Sport polyurethane, Racing polyurethane, and Solid aluminum! (Of course I believe it Brian, I just find it a bit nuts)

 

You don't want stiffer mounts unless you fancy some fab work...Early ('99) cars cracked their chassis mounts, they were then beefed up a bit, but it was just a token gesture. If you want eurothane you need to add strength to the frame mounting areas...

 

There is a 430 mount that will fit in the 360 trans because they are the very similar.

F1 cars will notice the trans mount going bad after 6500rpm shifts where the back end feels like its moving. You can take a mirror and place it close to the trans mount. If you see any tears its shot and so will be the engine mounts if not replaced soon after. It is a straight forward removal and install IF you have the right tools.