gm 12 bolt rear

Old 11-12-2009, 09:40 PM
  #1  
bowhay
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Default gm 12 bolt rear

how do u tell if its out of a truck or car?
and how can u tell what gears are in it already?
the number on it is nf 3896888 dont know id thatl help or not
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Old 11-12-2009, 11:19 PM
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cepx111
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Only thing I came up with that number was it's a portable electric hammer drill :shock:

hope this helps, Cp
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Old 11-12-2009, 11:22 PM
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cepx111
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You can pull the cover, count the ring gear teeth, divide that number into the pinion teeth.
Ball park ratio.

E.G ---> 39/7 = 5.571429 or what is commonly refered to as a 5.57 gear
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Old 11-13-2009, 11:24 AM
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bowhay
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ok its a 3.73
but how do i tel if its out of a truck or car, its 6 lug, did they even put 6 lugs on cars?
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Old 11-13-2009, 11:31 AM
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TopspeedLowet
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Truck has the smaller pinion shaft, car has the better larger pinion shaft and bearings. And if it has 6 lugs it aint no car axle if they are stock.
Bruce
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Old 11-13-2009, 01:01 PM
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FullTimeRacing
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car should have the rings for the 4 link bushing,or did the cars also have leafsprings too? :? :? :? ops: ops: ops:
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Old 11-13-2009, 01:31 PM
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TopspeedLowet
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Originally Posted by montecarlo84
car should have the rings for the 4 link bushing,or did the cars also have leafsprings too? :? :? :? ops: ops: ops:
Yes, The camaro, & Nova come to mind.
Bruce
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Old 11-14-2009, 06:45 AM
  #8  
bowhay
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ok cus the leaf mounts are at an angle on this 12 blt
and on my stock 10 bolt they r straight
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Old 11-14-2009, 04:42 PM
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Tod74
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Originally Posted by cepx111
Only thing I came up with that number was it's a portable electric hammer drill :shock:

hope this helps, Cp

hahahahaha
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Old 11-16-2009, 10:19 AM
  #10  
CamBirdRacing
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Originally Posted by bowhay
ok cus the leaf mounts are at an angle on this 12 blt
and on my stock 10 bolt they r straight

A truck the leaf mounts would be on the top of the housing as a F body will be on the bottom of the housing.
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