Hey guys, I've been trying to do a ring and pinion swap here at home and today I was measuring the wear pattern. The dial indicator said the backlash was .006". The manual says it should be .008" to .012". So I called a technition at a shop and he said that the backlash should be just fine after the new ring and pinion get broken in a little. But then when I went to measure the wear pattern with some Ratech, it seems way off of what the ford racing manual diagrams show.

Here is the link to the ford racing manual:
http://www.fordracingparts.com/downl...htM-4209-8.pdf
On page 26, it shows the patterns, I think mine might be "b".

I heard that you are supposed to apply a load of some sort when testing the wear patterns but I do not know how to do this. Could that be my problem? Should I try it again with a load? How?

Help! Thanks

 

All I gotta say is you are far braver than I. Differentials and transmissions guts (rebuild) are two things I never have nor ever will work on by myself.

Engines, I'll do those all day long along with FI or other drivetrain and suspension components but so much can go wrong after you put it all back together in the diff/tranny. No thanks,

Someone should chime in with some helpful info shortly.

 

It looks to me that you need a thinner pinion shim.

I am assuming you have your pinion bearing peload correct.

You will need to remove the pinion and pull the bearing , reshim. reset preload.

Once you reshim the pinion bearing , recheck your backlash I bet it will be closer to the .008"-.012" mark.
I almost always end up with .010" of backlash when every thing is set correctly.

 

Oh and they want you to apply a light load to the carrier , that way the gear will give you a clearer wear pattern in the ink. you can stick a screw driver in between the carrier casing and flange to apply a bit of drag on the carrier. I usually just hold the carrier with one hand while I spin the pinion with the other, it doesn't have to be a great deal of drag just enough to ensure the gear is pressing into the ink good.