Setting Ring and pinion
 

I'm replacing my open with a ZF I found. This is a 71 box. Any one know the spec's for the depth and side to side? Also where can I get a shim kit?
Thanks in advance.

Pinion depth will obviously remain the same, and backlash should be checked before removing your old diff, so that the new one can be set up with the identical backlash.

the depth doesn't change, because you don't mess with the pinion shaft. with a ZF posi, the dimensions are the same as the standard diff that was in there, so just use the original side shims in the same positions, and nothing will change. do a white grease contact check when you're done to ease your mind.

Thanks. Can some one give me the spec's though? I just want to make sure, for one thing I've forgotten what color gasket/spacer it was when I took the thing appart about a year ago. The other thing is this is a latter fine spline dif, so I want to approach this as a first time install.

whole different story now with the new info. the 915 diff can be made to fit, but it has to be offset to one side quite a bit, which makes the CVs run on the outside of their races. not the best idea. it would be a good idea to find a workshop manual that has the setup specs, as there's too much to type.

Bruce,

This is going to be one of those situations where your going to have to measure, shim and check the wipe pattern on the ring gear. I put a 915 quiafe in a 901 box this winter, and like John says one side will be offset quite a bit.

Take a look at the open spool once you have the bearings off, and compare the stub the bearing presses onto on each diff, it will be apparent that the zf will need many more shims on one side than the open diff.

Shims are available up to 3mm so shim out the side that needs the most shims with 3mm shims, and make up the difference withappropriate thinner shims. The assemble the diff, and check the wipe pattern...


ps: I have the workshop specs for a 901 trans, I could fax them on monday. let me know