Replacing differential mounts

[collins_dan]

I've been getting a bad vibration since a recent autocross. I looked at the differential from underneath (its so close it must be hitting) and the top of the mounts from inside the boot (rubber separated by a good 1/4 inch). I'm thinking the mounts need to be replaced. Is there an easy way to replace them without removing the differential? Thanks. Dan '70 S4 SE

[miked]

Dan,


Yes!

You should be able to undo the nuts from underneath on the bolts that drop down thro' the mount. Mole grips or a second person up top. You should then be able to pull out the bolts with the big top washers. You need to catch the spacer washer (s) that go in between the diff' and the mount bottom. See manual! You can then undo the two studs that hold each mount to the chassis. On most cars there is enough gap around the glass to lift out the old mount out. Use magnetic thing. If not, trim out. To fit new just reverse procedure.

It helps to slack off the torque rod nuts and separate those bushes as you can jiggle the diff' to allow alignment with the holes for the thro' bolts. One point is that I don't tighten the mount studs until I am through with the bolts and nuts back on as it helps when the can move the mounts a bit. Not a bad job. Back end lifted to access


Mike

[collins_dan]

Thanks Mike. All that's showing through the boot is just the tips of the mounts, so I should just trim away enough fiberglass to remove mounts from above. No way to remove them from below without removing differential? Dan

[RotoFlexible]

Thanks Mike. All that's showing through the boot is just the tips of the mounts, so I should just trim away enough fiberglass to remove mounts from above. No way to remove them from below without removing differential? Dan

No way to replace them from below, period. They mount to the top of the chassis crossmember and the body of the mount extends down through a hole in the crossmember that is too small to pass the mounting flange. If the nuts and bolts are not corroded in place, this is not a difficult job - relative to some others.

[alan71]

I was getting a bit of movement from my diff, found that it had dropped on it?s mounts and the torque rod rubber bushes had gone soft.
The bolts were fitted from below so you could remove the mounts from above but you can?t add the big washers, they don?t fit through the hole in the chassis. I had to cut the bolt heads off, found both bolts slightly bent.

Alan.

[miked]

Yep,
if the bolts are fitted from below they are baulked by the drive gear. That's why they are dropped in from above. That way you just fit the nuts. One other point is that if you have the sprint cross brace, this acts like a washer and you may not need any in this position.

Mike