Diff mounts

[paddy]

The car developed a knocking today, coming from the rear of the car, and occurring particularly on overrun or when pulling away in reverse.

I've had a look at the diff and its mountings. The clearance at the top is > 1/4" but the clearance underneath is very small. The diff can be made to move up and down quite easily by between 1/8" and 1/4" with a crowbar between it and the chassis (the movement being of the whole unit, not just the nose).

The top mounts were replaced recently (according to the PO) and have done no more than 2000 miles but there is a lot of movement - is this normal? I haven't tried removing the mounts yet, but is this perhaps another case of new spec rubber parts not bonding as well as the old ones?

What do people recommend for replacements? It's only for road use. I have CV joints so should I try to preserve what little driveline cushioning I still have or go for harder bushes?

Paddy

[elansprint71]

Tony Thompson Racing has heavy duty diff mounts; there have been several threads about this, please check the archives.

[paddy]

OK, thanks. Sounds like a diff brace is also worth the investment.

Paddy

[collins_dan]

I replaced my diff mounts this past weekend. After installing, I gently jacked up the differential directly underneath each mount and tightened the nut on top. I still only have very slight clearance at the bottom, but nothing is moving around. Also, make sure you have good bushings, mine were trashed. I was also amazed at the amount of dirt that was basically glued to the frame under the diff by old oil. I need to get an air compressor in there and blow it all clear to see just how much clearance I actually have. Dan