I'm doing a gear/ posi installation on a 8.5" 10 bolt, and I'd like some advice on the contact patterns.

This is with .005" backlash:





Here it is with .010" backlash:





I know that neither of those are right. It kind of looks like the pinion should go in a little more. What do y'all think?

 

Okay, I pressed off the pinion bearing and removed the .035" factory shim, and added a .039" shim.

This is the pattern with .006" backlash:







I showed these pictures to some guys at work today, and they said that the pattern looked good (based on a phone picture), so unless anyone has any objections, I'm going to run it.

 

Zero experience setting up rear ends here but the 3rd pattern definitely looks much better than the first two to me.

 

You tube has a lot of videos on this from the 4x4 guys.
If you can find a copy the Dana service manual is great for gear pics and setup.

 

Sorry if I missed it, what gears are these and new or used?

 

What kind of posi is that?

 

looks like a gov-bomb G80

 

OP,
After looking at this thread the other day, I started checking out various gear vendors sites. I found some good articles on selling up the gears.

it Ishtar be worth investigating