The Stovebolt Site Forums The Shop Area Driveline 1948 3600 Axle swap

I am looking for the best fitting updated 8 lug rear axle for my truck. I'm looking for one that can use my original wheels.

73-88 Chevy 14 bolt. They had a dually model that was 63" WMS-WMS. Which is pretty much dead on what yours is. They are a little hard to come by though. The 14 bolt that was in Single wheeled 3/4 ton and 1 tons will also work. They are refered to as the 67" axle.

You can use the hubs off of your Eaton rearend on the 14 bolt, you'll just need to get the correct bearings. I can get that info if you want. With this setup you'll have around a 65 WMS, which is perfectly fine. You'll have to adapt the brakes to work though. GM had quite a few different brake drum setups, so it shouldn't be a really big issue.

The 15" rims like the 3600's used will fit over the 14 bolt hubs and clear the drums only on the models with the drums on the backside of the hub. The 15" wheels won't work the drums that are slip on.

Can I use the complete rear end, brakes axles and all?

Yes, the 63" dually rear would be best.

Some guys have used Dana 60's from Dodge vans also.

Either way, you're going to need different axle perches also.

I found a 1979 14 bolt with 4:10 gears local for $300. Other than changing the spring perches and rigging the brake cable, is there anything I must do?

I believe the brake cable is a direct swap, no real issues there.

I would put some wheel seals in and check the bearings, that's about it.

These axles were stout.

If you get the dually rear, you'll need to cut your wheel studs down shorter or just get some for the single wheel trucks.

If found a 63" from a 1979 dually, I am picking up tonight.

I brought home the 63" dually rear end. I will not fit, backing plate to backing plate is to narrow. The new one measures 44" between plates. The truck is 44 1/2 to the outside of the leaf springs...WTF?

Well, I guess I mislead you a little bit. I have a 67" rearend that I put narrower hubs on. I had a junk 63" that I pulled the hubs off of. I never did measure drum to drum.

I believe I've seen other members with the 63" rearend. Hmmm....

GM did make a few different brake setups.

You may need drums from a 3/4 ton truck and move your backing plates it. I think you can also mount your drum on the front side of the hub vs. the the rear.

On a side note, I have found that swapping to the Eaton hubs is a good alternative too. You'll have to get different bearings though. The Eaton stub shaft is .060 bigger. (I have bearing numbers if interested) Originally I thought it would make the axle around 65" wide, but it looks like it'll be somewhere in the 64-64.5 range. Just something to think about.