63 GMC rear end swap options?

[bigmoe]

I just acquired a 63. Plans are to restomod it with a slight height drop. I've been doing a ton of reading here trying to edumacate muhself, lol. I'd like to do the 73-87 front crossmember swap to convert the front end to power steering and disc brakes. With 5 lug hubs it will give more options for wheels. What are my options for a 5 bolt rear end to fit this truck?

[Clyde65]

Just get the 5 lug axles, Mosier has them for 65-69, better spline count. They should fit but ask first!

http://www.moserengineering.com/1965...evy-Truck.dept

[Captainfab]

With the '63 & '64 truck 12 bolt, converting to 5 lug axles becomes a little more expensive than for the '65-'70 truck 12 bolt. This is because the spider gears must also be changed to accommodate the new conversion axles. The '71-'72 truck 12 bolt will be a direct bolt in except for the panhard bar. The '73-'82 truck 12 bolt and '79-'87 truck 10 bolt can work but require cutting off the leaf spring perches and shock mounts and welding on trailing arm mounts while keeping the correct pinion angle. The '71-'87 truck 10 and 12 bolts are 1.5" wider than your current '63 truck 12 bolt.

[61K10]

63 GMC not a Dana?

[Grounded63]

I swapped a '81 half ton 10 bolt into my '63 chevy. I like the slightly wider stance, of the " newer " rear end. If you swap rear ends, you can also get one with a more highway friendly gear set, if wanted. Killing two birds with one stone. With my swap the drive shaft needed shortening, so be aware of that also.

[bigmoe]

Here's a couple of pics. 12 bolts. It's supposed to have pressed on backing plates for 63 but I see four bolts. Does that mean bolt on backing plates?

[Grounded63]

Yes, looks like it already been swaped to a newer 12 bolt.

[bigmoe]

Hmmm. So if it's the newer 30 spline axles then I could buy Moser axles to convert to 5 bolt. I guess the only way to tell is to pull an axle.

[Grounded63]

They should be, my understanding is that '64 and up 12 bolts are 30 spline. Except for maybe a few early/mid year '64 exceptions.

[Captainfab]

That is a '65-'70 truck 12 bolt which will have the 30 spline axles and spider gears. So yes you can simply buy a set of 5 lug conversion axles from Moser or any other manufacturer or vendor.

Also a '63 GMC should have leaf springs in the rear. It is possible that it could have been special ordered that way, someone converted it to trailing arms and coil springs, or the frame is not original to the cab.