Rear end build
Thread Starter
Teching In
Joined: Aug 2012
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Rear end build Hey guy's, this is my first time swapping a ring and pinion and I was wondering if anyone with more experiance could comment on the pattern? Yeah, it's another one of those threads, lol. I've read and looked at a lot of other pics, was just hoping to get opinions on mine, cell phone pics aren't the greatist though.
That being said they are used GM 3.73's (probably from an s-10 judging from the sellars other stuff) on a used Torsen (supposedly from a 02 camaro, 65k mi.) in a stock thirdgen (89) housing. Low mile (65k) set-up bearings on the pinion right now, preload @ 20 in.lbs. Backlash is .009 right now. This is with the stock pinion shim that came in the housing. I tried the 89 housing carrier shims but they only provided .004 backlash so I opened it up a little. What would be a good backlash to run for used GM gears anyway?
That being said they are used GM 3.73's (probably from an s-10 judging from the sellars other stuff) on a used Torsen (supposedly from a 02 camaro, 65k mi.) in a stock thirdgen (89) housing. Low mile (65k) set-up bearings on the pinion right now, preload @ 20 in.lbs. Backlash is .009 right now. This is with the stock pinion shim that came in the housing. I tried the 89 housing carrier shims but they only provided .004 backlash so I opened it up a little. What would be a good backlash to run for used GM gears anyway?
it realy close and would work like you have it, .oo9 is with in spec for back lash, in my opinnion the drive side pattern is just a little high, if i remember if you take out about 2 or 3 thousands from the current pinion shim you have now, it lower your drive pattern a little more to the center and loosen up the backlash a little, i would keep back lash from .008 to .012.
Thread Starter
Teching In
Joined: Aug 2012
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Thanks for the reply, I think I'll take .004 off the pinion shim and see what it looks like. I'ts .039 now, and I have .035 and a .031 factory shims, plus the shims in the rebuild kit.
I'm afraid the new bearings are going to be a couple thousandth's different from the setup bearings anyway.
I'm afraid the new bearings are going to be a couple thousandth's different from the setup bearings anyway.
Thread Starter
Teching In
Joined: Aug 2012
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This morning I got to work on the rear a little more. I changed the pinion shim from .039 to .035 and reassembled. Same 20 in. lbs. pinion preload and same .009 backlash. I think the drive side looks pretty good, both sides are more centered between the heel and toe. Does anyone think the coast side is to close to the crown now?
Im definitely not an expert, hell im not even a respectable novice, but my understanding is heel to toe centering is basically irrelevant and you need to concentrate on centering flank to face...so imo your first patterns were better. Maybe this thread containing one of my many public shamings will be helpful to you...although it seems like youre doing pretty well.
https://ls1tech.com/forums/gears-axles/1541712-anyone-care-read-my-paint.html
https://ls1tech.com/forums/gears-axles/1541712-anyone-care-read-my-paint.html
TECH Regular
Joined: Oct 2011
Posts: 407
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From: Keller Tx
Looks like it could be a tad deeper on the ring but I think you are right there. You could run that and it may not whine. Your coast looks better. I ran mine with .005 BL and it worked out for me. I figure over time it would losen up a bit anyway.
