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Old 04-02-2010, 12:44 PM
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12 bolt pattern

Been trying to get the pattern setup just right on the new 3.73 ring and pinion. Backlash is at .009 (.010 recommended) and it looks pretty close to what Richmond shows in their pattern diagram but I am not sure when I look at other pattern guides. Anybody have an opinion?
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Last edited by chipflyer; 04-02-2010 at 03:19 PM.
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Old 04-02-2010, 02:17 PM
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It's a little hard to say from that picture, but it looks close. The pinion might be a little too deep. Please take a closer picture of the drive side and the coast side so that I can see more details of both.
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Old 04-02-2010, 02:59 PM
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These might help
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Old 04-02-2010, 03:06 PM
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I'd run it. Pinion might need a bit thinner shim, but this tends to be "self correcting" under a load, in my experience. But then, I don't do this for a living.

Last edited by cobalt327; 04-02-2010 at 03:11 PM.
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Old 04-02-2010, 03:12 PM
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If you look at a lot of other pattern diagrams it looks like it might be a bit deep, but the color instruction sheet the came with the Richmond gears only shows one acceptable pattern and it is pretty close to this. They recommend .010 - .014 on the end play and after lots of tweaking its a .009 with a nice tight fit.
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Old 04-02-2010, 03:23 PM
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Quote:
Originally Posted by chipflyer
They recommend .010 - .014 on the end play and after lots of tweaking its a .009 with a nice tight fit.
If by end play you're talking about backlash, 0.009" should be OK w/new gears, IMO.
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Old 04-02-2010, 03:25 PM
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Pinion might be .002" too close. If you move it that much you'll pick up a little backlash too.
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Old 04-02-2010, 04:06 PM
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Whoops Cobalt, I meant backlash. I do have a bit of preload on the diff bearings.
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Old 04-02-2010, 09:31 PM
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The coast pattern shows that the pinion is too deep. Try removing about .002 to .003 from the pinion shim and try again.
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