Questions about rear axle interchange

[beaterC10]

I have a chance to buy a 3:73 geared 12 bolt rear axle with an Auburn limited slip from a 79 1/2 4X4 at a reasonable price.

The two issues that come to mind are the fact the 4x4 will be 6 lug and the yoke might be larger than on my 10 bolt. Can I use the axles from my 10 bolt in the 12 bolt rear? Does anyone know if the yokes are different sizes. Are all the 73-87 1/2 rear ends a bolt in interchange? Thanks

[hiway]

From your ten bolt to a 12 bolt is just a different u-joint. Precision 369 seems right ....or something like that. Axles and yokes are different and won't interchange. As far as it being 6 lug, they make adapters (adds width and generally weaker) or you could find some 5 lug axles. Your 10's backing plate and brake stuff should work though. What are they asking $$$$?

[beaterC10]

Originally Posted by hiway

From your ten bolt to a 12 bolt is just a different u-joint. Precision 369 seems right ....or something like that. Axles and yokes are different and won't interchange. As far as it being 6 lug, they make adapters (adds width and generally weaker) or you could find some 5 lug axles. Your 10's backing plate and brake stuff should work though. What are they asking $$$$?

I can get the rear end for $150 maybe less. The ltd slip is supposed to be less than 1 year old. I was primarily looking for a 3:73 rear gear.

[Srubydo1986]

Im about to buy one as well he ask 150 for it or i could trade so im trading him my one ton 4x4 axels for it cause i dont need them to low i like my 373s

[piecesparts]

I purchased a 4X4 12 bolt rear end with the 3.73 posi in it for my Son's truck. We pulled the 6 bolt axles out and the salvage yard had 5 bolt axles there to put back into it. Be sure to get the right length for that axle, there are three or four different length axle shafts. You will have to buy a new yoke, they are not that expensive. Check to see that your driveline is the right length. The 12 bolt pumpkin seems to be a little different in length than the 10 bolt units. If you are getting it for $150.00, I would recommend taking it apart enough to look at your carrier bearings and posi parts. That sounds way TO good to believe. Most salvage yards are asking $600.00 to $1000.00 for a good axle.

DO NOT USE adapters, if you don't have to.

[beaterC10]

Originally Posted by piecesparts

I purchased a 4X4 12 bolt rear end with the 3.73 posi in it for my Son's truck. We pulled the 6 bolt axles out and the salvage yard had 5 bolt axles there to put back into it. Be sure to get the right length for that axle, there are three or four different length axle shafts. You will have to buy a new yoke, they are not that expensive. Check to see that your driveline is the right length. The 12 bolt pumpkin seems to be a little different in length than the 10 bolt units. If you are getting it for $150.00, I would recommend taking it apart enough to look at your carrier bearings and posi parts. That sounds way TO good to believe. Most salvage yards are asking $600.00 to $1000.00 for a good axle.

DO NOT USE adapters, if you don't have to.

Any idea what a used set of axle shafts should cost? This purchase would be from an individual, so I would need to buy set of axles or have these drilled for 5-lug.

Are recommending chnanging the yoke to match the driveshaft instead of using a u-joint with different sized caps?

[hiway]

Like was said...check the width. Regular 12bolt axles at a salvage yard around hear would be around $100 or so. Seems like $300 would buy new ones. I'm not real sure if you can redrill due to the holes falling on top of each other. The "adapter" u-joint is around $20 or maybe a little more. A yoke would probably be slightly more. Your call. Just as a comparison...I gave $200 for just my posi unit used. Complete 12bolts or 10's are between $150-$450 depending on ratio and posi or not. Arkansas of course.

[piecesparts]

I wonder where these cheap axles were, when I was looking for one. I am here to tell you that they do NOT go for the prices that I see on here, in my area of the country. I checked numerous salvage outlets and they seemed to come at a higher cost than that. As for the used axles, I agree on the price marked above, but the ones that were put in my rear end were part of the deal to get a posi 12 bolt set up.