I've been rebuilding my original '85 10 bolt since the spiders in the old diff were chipped, among other issues from it being abused over 30 years lol. In any case, I sourced a 2000 torsen unit, 28 spline axles, and 3.73 ring/pinion set. I've got all my backlash, and gear pattern set up near perfect, and started to finally put everything back together the last time. I've got a couple questions:

1 - My original bolt, that holds the large pin in the diff, has broken (as they usually do). Is there anywhere I can source a new one? This thread shows exactly the bolt I'm talking about, and lists a part number near the bottom: http://www.nastyz28.com/forum/showthread.php?t=107063
Are the bolts all the same threaded length? For instance, if I found one for my old auburn unit, would it fit m '00 torsen diff too?
EDIT: It turns out Rockauto DOES carry this part, you can search by part number "14056196" and it'll show up as a Dorman part, named "Differential Pinion Shaft Lock Bolt" and pn#81048. I'm still uncertain whether this bolt fits ALL carriers including my torsen tho.

2 - I've searched high and low to gather all possible information regarding pinion torque, bearing preload, and approximate drag while spinning the pinion/yoke. I'm interested in more opinions on how the drag on the pinion should "feel" when it's properly set up. In the following thread, one poster said it should be able to spin 1-2 revolutions on its own, even with the bearings properly preloaded (https://www.thirdgen.org/forums/tran...g-preload.html). Most folks I talk to say it should actually be more difficult to spin, that it shouldn't spin much freely at all.
Currently, I've put a ton of muscle into tightening the pinion nut, and my in-lbs beam type tq wrench shows ~5inlbs dynamic torque(to keep it turning). I would describe the pinion drag as being tight/snug...it'll barely spin 1 revolution if I spin and let go. I would like to get at least 15inlbs preload on these new bearings, but I feel as if the drag will be too tight at that point. What do you think? Thanks for any and all input, I hope this helps clarify things for others besides myself!

 

Go to GM for the bolt. Don't screw around with that Dorman crap. Go to GM for the better quality part.

If anyone tells you that the pinion should spin free after setting the preload on new pinion bearings then stick your fingers in your ears and run away from them quickly before any more of their stupidity gets into your brain. That is completely WRONG. The preload on new bearings should be at least 15 inch pounds, and closer to 19. Go ahead and tighten the nut some more and do it right. This is too much for used bearings, but new bearings need the extra preload.

 

It should not spin very much on its own if you just flick it with your wrist; maybe not even a half rev.

I prefer to set mine up at a tiny bit more preload than 19, maybe as much as 24 w new bearings. (might be as little as 19 if the seal wasn't there but then you'd have to take it apart and put the seal and a new crush sleeve in, so that doesn't make much sense) It's not all that significant a difference though. It often only takes as little as 150 ft-lbs on the nut to get the desired preload, which is why I prefer to use a "crush sleeve eliminator" aka solid spacer with shims: that allows the nut to be tightened as tight as you want because you don't have to stop when the preload is reached.

 

Thanks guys! I just set it tonight, 20inlbs preload. I'll button everything up soon and put it back under the car!