When I got my rear end 5 years ago it only had one shim left in the fulcrum shaft mounts.
Of course the rear end come apart and was cleaned up for my tbucket.
Someone awhile back told me how to put the correct shims in there. But I can't remember who.
I took my rear end apart for a new paint job. Not thinking I mixed the shims up. Now I can't remember how they went.
I have some .007 and .005 horse shoe shims.

 

I think you are referring to the two long forgings that bolt to the sides of the diff and form the mounts for the lower wishbone inner pivots? (there are a number of other fulcrums with shims in the rear axle!)

The purpose of the shims is to ensure perfect alignment, when bolted up tight, of the holes in the casting and the holes in the lower wishbone arm inner end and the holes in the axle cage. This is so there is no possibility of the "hinge" binding in use.The shims go between the casting and the diff and are inserted from the top so they cannot fall out. If the alignment is correct, the actual fulcrum pin that goes through the bearings in the wishbone arm, holds the lot together and is bolted up each end, can be pushed into place quite easily. Trial end error is basically how it is done.

For some reason these forgings tend to come loose with use, so Loctite-ing and safety wiring the bolts is a good plan.

Greg

 

Greg has nailed it.

LOTS of trial and error in getting them correct.

I generally secure the 4 top mounting bolts, Loctite and wire, then upend the cradle, position the cast brackets onto the diff casing and leave the 4 bolts LOOSE. Slide the LONG pivot shaft thru the cradle, and the castings, and out the other end.

Now SLOWLY tighten the bolts, usually finger tight for now. Measure the shim needed, ADD 0.002" to that measurement, and fit selected shim/s, and tighten the 2 bolts. Now do the other side.

Now you need a SERIOUS drink. Atempt to slide those long pins OUT. If they simply slide out, you are a bloody GENIUS, but I bet they dont. SO now Gregs "fiddle factor" comes into play, and removing/adding shims to those bolts so those pins slide in/out without the use a BFH is achieved.

Once sorted, and the drinks have been taken, slide the pins out, remove ONE bolt at a time and Loctite them back into place and wire as needed.

Now refit the arms with the seals etc, and slide those pins in, secure the nuts on each end, and you are done.

This usually takes me a full day just to set that up the proper way.

Lots of shortcuts out there, but the proper way makes that rear end perform exactly as designed, and that is a sweet thing, even in a T Bucket.

 

Yep that's what I'm referring to.

Now I don't have the cage any more.
:-)

I'll get the rear end back under my bucket this weekend and see
how things go.

 

So what is the inner wishbone and diff suspended from ?


Greg

 

OH?

 

The cage isn't necessary if the differential housing is secured top and bottom by other means. The cage only exists in Jaguars to ease installation as a sub assembly, it's far from an excellent piece of engineering.

 

Soooooo, without that piece of excellent engineering the need for said shims has gone out the window.

Simply bolt the cast brackets to the diff casing, much better than the shim idea anyway, and slide the long pivot pins into place and measure/make the "cradle" to suit.

Probably even do away with that crush tube, so access to those bolts would be possible in the future without dismantling the pivot pins.

 

Most interesting, How will you secure the diff bottom to your new chassis piece?.


Greg

 

But don't them shims also control toe in/out.

When I get my rear end back in I'll post a pic.
Here is one of it hanging.