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Gear pattern experts HELP!!!

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Old Apr 3, 2010 | 12:56 PM
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Default Gear pattern experts HELP!!!

Broke my Motive 3.73 gears in my 10 bolt rear-end last fall. I have a buddy who had a used set of Motive 4.10 gears he gave to me. This is my first gear install so I used the original pinion shim to get me in the ballpark and have backlash set @.009 and this is the pattern I am getting...







What is causing the odd pattern on the coast side? How does the drive side look for used gears? Are the gears junk or do I need to start from scratch? Thanks for any advice!

Jeff
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Old Apr 3, 2010 | 02:12 PM
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you're applying too much compound,a very thin light coat will do. Too much will smear and hide/mask the true pattern. Even though the pattern needs change,reduce the compound.
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Old Apr 3, 2010 | 07:51 PM
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Your pinon is too deep according to your pattern marks, did you measure your new pinion depth or did you reuse your old pinon shims?
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Old Apr 4, 2010 | 08:56 AM
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Yeah, agreed, can you get us another set of pics?? The coast side looks like its falling off the edge of the tooth.
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Old Apr 5, 2010 | 04:44 PM
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That is the pattern I get over and over. Yes, I used the stock pinion shim. I assembled the rest of the rear and drove it about 1500 feet and at 20+mph is makes an aweful grinding/growling noise.
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Old Apr 6, 2010 | 06:17 AM
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Never try to use used gears. I never works. Or very rarely. And you only need the compound on about 5 teeth.
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Old Apr 6, 2010 | 07:51 AM
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Yeah using stock shims will never line up with a another set of gears. You need to measure your stock pinion shim and take a few thousands off, unless you have the correct Pinion depth tool.
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Old Apr 17, 2010 | 03:47 PM
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Default Update!

I measured my stock pinion shim at .030". I installed a new shim of .017" (thinnest pinion shim in motive gear install kit). Backlash is a little on the tight side at around .006". My pattern still looks like crap!!! Any other ideas or should I junk these used gears and start over with a new set? Thanks again for any advice!

Jeff





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Old Apr 18, 2010 | 05:44 PM
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sorry about your luck, but unless you have the backlash and pattern from the original rear end the gears were ran in, it will never work. you can get a great pattern, but that doesnt mean thats where it was setup originaly.
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