arb and R&P install ?s

[erfworm]

Started putting in the locker and gears today and a couple of questions popped up.
First, when I removed the pinion gear, there were no shims behind the inner bearing race. Has anyone ever run across zero shim tolerances before. Should I set initial pinion preload with no shim at first. Is there an accurate method of measuring old pinion and new pinion depths/lengths to find a starting point.
Second, where is the best or your favorite place to drill the hole for the ARB air fitting. The ARB manual shows a spot in the upper right hand (looking at the gears) area of the carrier, but I'm not sure if those are just stock photos of xdiff in xvehicle.
Any thoughts, reccomendations, and pics are greatly appreciated.

 

[FJ60Cam]

ARB air fitting

I sent my third to Kurt (Cruiseroutfitters) for the differential rebuild/ARB install. Here's where he tapped into it...

 

[Barry822]

Are you changing ratios? Your new pinion should be marked for nominal depth, usually on the tooth end of the pinion. Thats where you start and set your pattern form there. Good luck.

 

[Barry822]

Your pinion bearing preload is set by your crush sleeve not your shims. Your shims move the pinion in or out.

 

[Tapage]

Mine ..

and old pic ..

 

[Tinker]

User -
Did you or Kurt powder coat the 3rd?

 

[FJ60Cam]

User -
Did you or Kurt powder coat the 3rd?

I just cleaned them up with brake cleaner, mineral spirits and a toothbrush, then put about three coats of spraycan rustoleum satin.

 

[KLF]

Exactly where I put mine:

Be careful when drilling and tapping the housing, the cast iron is really soft.

Yup, three coats of Rustoleum, good stuff.

 

[erfworm]

Are you changing ratios? Your new pinion should be marked for nominal depth, usually on the tooth end of the pinion. Thats where you start and set your pattern form there. Good luck.

Barry, the only markings I see are on the pinion shaft and read as follows: 580/05 and 8x39, not sure what those mean? Sierra gears if that matters.

That makes sense that the shimming only moves the pinion in and out for proper pattern, I guess that I was thinking that the preload would be affected by the shim thickness behind the inner bearing race.

Thanks for the pics guys, that is pretty much the same area that the ARB manual shows, just wanted some friendly confirmation.

 

[Barry822]

Not too sure what those numbers mean. The 8/39 sounds like a tooth count of the pinion and ring. The nominal depth number is usually just a single digit with a plus or minus. You could try calling the manufacturer tech help line. Best of luck.

 

[Tapage]

Barry, the only markings I see are on the pinion shaft and read as follows: 580/05 and 8x39, not sure what those mean?

4.875 = 4.88 !