Buick 12 bolt rear end problem

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Ricky
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Buick 12 bolt rear end problem

Post by Ricky »

Hi i have problem with My 12 bolted rear end on My buick skylark -68.
Its a c-clip axel and when the tiers are in the air i can pull the wheel in and out like 3-4mm
Does any one know if the Axels are worn out or is the c-clip worn?? I toke it all apart but i cant see anything wrong with it.
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monzaz
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Re: Buick 12 bolt rear end problem

Post by monzaz »

Is the diff posi? or just a open single wheel peel. There will ALWAYS be end play on the c-clip axle rears. WHICH IS A CHEVY 12 bolt

.005-.035 is normal for end play - when you start to get a lot more than that you need to find out what is wearing. The axle button end will wear. The clutches in the posi unit will wear causing more end play. spider gears will wear causing more end play. UP and down play is bad this means you have slop or wear in the bearing to axle ride surface. IF the axle has a groove worn into the surface where it meets the bearing you need to replace the axle. If the button end where the c-clip has a very sharp edge or metal flashing sharp...it is wearing too. Hard long turns like circle track and road racing or lots of miles on the rear will cause this.

Jim
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Ricky
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Re: Buick 12 bolt rear end problem

Post by Ricky »

I just replaced My wheel bearing. And i didnt feel any wearing at the c-clip so i think it Will have to be the axels or spider gears. My rear end play is about .060-.070. But doesent feel or hear anything while driving.
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monzaz
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Re: Buick 12 bolt rear end problem

Post by monzaz »

Well being that a c-clip is .125 you can see where this will be an issue sooner or later. If it is a Posi rear with clutches i would say you need to reshim the clutch pack. Jim
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Ricky
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Re: Buick 12 bolt rear end problem

Post by Ricky »

Yes it is a posi with clutch, so u think it is the clutch that is the problem?
If u reschim the clutch does the spidergears move a litle so the gape gets smaller?
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monzaz
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Re: Buick 12 bolt rear end problem

Post by monzaz »

Yes when you have the proper shimmed Eaton posi it will bring back the spider gear backlash tighter again and also move both side gears toward the center pin again taking up the slack in the axle shaft c-clip button slot to the side gear recessed pocket and CArrier pinion shaft center pin the end of the axle shaft butts up against.

If you remove the posi and take an axle shaft and clamp the shaft in a vice so the slip is up and you can insert the posi unit onto the spline and this will help you twist the spider gear in and out of the cavity of the posi unit once you remove the preload springs and cage.

You want the spiders in the posi to be as tight as you can to spin them in with the axle shaft ...It is a bit tricky at first BUT you will get the idea once you tinker with it a bit. :) Jim
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monzaz
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Re: Buick 12 bolt rear end problem

Post by monzaz »

We have posi shim kits also if you need shims PM me I will price them for you.
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