Author Topic: rear axle swap question  (Read 2816 times)

Offline 81GMCBILL

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rear axle swap question
« on: January 13, 2012, 11:19:53 pm »
long story short.. a couple of months ago I knowingly bought this 81 GMC k3500 having
a rear axle 10.5"ring gear-14 bolt- 4.56 ratio and that the front axle had a swapped in
10-bolt axle -8.5"gear - 4.10 ring gear.   Now in saying this, the thought was that i could easily
change the ring & pinion in the front, but in reading some of the posts - it would be better
to change the whole axle out than to change out the gears. I found for sale a rearend on
 a 78 chev 3/4 ton axle w/4.10 gears -the question here is> Would this bolt up with my 81 gmc
as in the shock mounting, length and such ?

Anyways -I am at a crossroad on what my options are here.

thanks all.
85 GMC K25 4X4 383/th400/np208

Offline Blazin

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Re: rear axle swap question
« Reply #1 on: January 13, 2012, 11:25:31 pm »
You should swap in the correct front end for the truck. If its a true 3500 it would have had a Dana 60 front axle. A 60 is about 20 times stronger than a 10 bolt.
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Offline bake74

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Re: rear axle swap question
« Reply #2 on: January 14, 2012, 07:31:54 am »
You should swap in the correct front end for the truck. If its a true 3500 it would have had a Dana 60 front axle. A 60 is about 20 times stronger than a 10 bolt.

     Abbsole freaking luitly, why downgrade to a 3/4 ton running gear when you are suppose to have 1 ton running gear.   ???
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Offline 81GMCBILL

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Re: rear axle swap question
« Reply #3 on: January 16, 2012, 10:47:31 pm »
yea -your right about the Dana 60 - but at this time im looking at a quick fix til I can get to finding then replacing the front axle this summer.
But yea thanks for straightening me out .
85 GMC K25 4X4 383/th400/np208