hawkman199

Here is a video of how much the rear diff mount moves during driving.

https://www.youtube....h?v=gMJJPqdCC2c

I guess someone mounted a camera under the car and went for a drive.

It's amazing how much deflection there is!

myflys2k

Wow. I'd probably go the route of diff collars.

zeroptzero

I got under the rear end of the car tonight, and every thing looks dry. I don't see anything that resembles any kind of seepage. I do remember seeing brownish drip stains on the my last exhaust before I sold it. Looking at the two rear mounts they look clean and dry.

hawkman199

So I took the rear diff mount off last night and took some photos.

I thought it was the passenger side, but in my dyslexia, I got the side wrong. It was the drivers side, which is the most common to go.

So, to take off the diff mounts:
1. Jack up the rear of the car and put stands under the subframe.
2. Take off the rear wheels.
3. Unbolt the sway bar.
4. Slip the exhaust muffler mounts off, support the exhaust with a jack.
5. Unbolt both rear diff mounts.
6. Place another jack under the diff and lower it down, so you can slip the diff mounts off.
[attachment=84647:Jack under exhaust.JPG]

Jack under exhaust
[attachment=84648:Jack under diff.JPG]

Jack under diff
[attachment=84649:Screwdriver in split.JPG]

Big split in top of mount pointing to rear of car
[attachment=84650:Split and trimmed.JPG]

Trimmed damaged area
[attachment=84651:Blow out solvent.JPG]

Clean out with brake cleaner and blow out with compressed air to dry
[attachment=84652:Starting fill.JPG]

Fill slowly to get out as much air as possible, tap with rubber mallet to settle and get air bubbles out.
[attachment=84653:Filled.JPG]

Filled. Cure for 24-48 hours. The urethane is paintable.

myflys2k

The stuff I used was black. Got it at Napa. I'm not sure how well paint will hold up on the flexible mount

iDomN8U

Not sure if it would have any impact however M&M are testing a rear Diff brace, maybe that's why it's putting more movement through the mounts?

hawkman199

Yeah, it's not too pretty.

Will see how the enamel paint holds up.

Gonna change the diff fluid while I'm there.

RB

zeroptzero

Robin, did you find that the mount was torn from the surface that faces the rear of the vehicle, or the surface that faces the front of the vehicle ?. Could you see the damaged mount when you were under the car with everything fully installed, or was it only visible once you got the mounts removed ?.

hawkman199

Hi Joey, the mount was torn towards the rear of the car and was actually split just below the joint between the rubber and the outer steel ring or collar.

I suspect there was an initial small tear, which is why the oil squirted out with enough force to splash against the trunk.

After that, the tear would just spread. The edge or point of any crack in any material is a point of infinite stress, which is why cracks propagate, if the material is soft it will propagate more slowly than if the material is hard.

It is a little difficult to see a crack with the mount in the car. However, if there is fluid around or near the mount, one of the two oil containing chambers is damaged.

I put everything back together yesterday. Took about 45 minutes.

Drove the car to work today. Feels fine.

Hope this helps!

RB

zeroptzero

Thanks Robin. I'm just thinking that if mine leaked it may have leaked a long time ago, and everything looks dry under there now. I can't see any tear from the backside but like you said it is hard to see up there with everything installed. The only sign I remember was some odd looking brown stains on the exhaust pipe.

Thanks for the post, very informative