12 bolt rear question

[OldChevy61]

When I started building my 62, I ditched the ho32 and replaced with a 12 bolt. Casting no,s came back as 63,64, 3,73, non posi. It is a 6 lug. My son just bought a 66 c/10, has a 12 bolt ,3.73,non posi. Two totaly different differential covers. His is clearly truck, mine has the cover of a car rearend. When I bought it, was out of the vehicle so no way to know what it actually came out of. Whatever it was had trailing arms and panhard bar, measured the same as my 62 rearend, Just had to move the mounting pads and panhard bracket. Was there any Cars in that time that used a 6 lug rear? It works real good , just curious as to what it may have came out of or if the earlier ones were different.

[chevykid65]

In a 6 lug it could only be 1/2 ton pickup. Cars were all 5 lug. Trailing arm and panhard would be 60-72. 70-72 were a wider rear end though.

[Captainfab]

If it does have a car 12 bolt cover but yet has 6 lug axles trailing arm mounts and a panhard bar mount, it sounds like someone has built this differential to fit their needs. The Impala/Caprice 12 bolt has the car 12 bolt cover but has the same housing ends as a truck 12 bolt. I have not seen one of these that is the same width as a '63-'70 truck 12 bolt from the factory, but it is possible.

[OldChevy61]

Originally Posted by Captainfab

If it does have a car 12 bolt cover but yet has 6 lug axles trailing arm mounts and a panhard bar mount, it sounds like someone has built this differential to fit their needs. The Impala/Caprice 12 bolt has the car 12 bolt cover but has the same housing ends as a truck 12 bolt. I have not seen one of these that is the same width as a '63-'70 truck 12 bolt from the factory, but it is possible.

I will get some pics and measurements of both rears if rain lets off later. When I got it, it had the same ebrake cables and used the truck brake drums and shoes.Rear did not look like it had any work done to it pryor, but who knows,lol.Measured the same as the ho32 mounting surface to mounting surface.

[OldChevy61]

ok, so Im the dummy here. I could have sworn mine had a car cover on it. been awhile since I was under it. Just a truck 12 bolt. At least it has bolted on backing plates instead of press on.lol

[ratskin]

1963 and 64 were bastard rear ends with 17 splines. No one makes axles for them, so to go to five lug, I went to a complete 71-72. I also could have used 65 or 66 and bought axles. I think the panhard bars may be different also.

[OldChevy61]

Originally Posted by ratskin

1963 and 64 were bastard rear ends with 17 splines. No one makes axles for them, so to go to five lug, I went to a complete 71-72. I also could have used 65 or 66 and bought axles. I think the panhard bars may be different also.

not looking to go 5 lug, was just curious to what it may be.

[chevykid65]

Its like most of the parts under my truck. I don't worry about them until they start giving me trouble. Like today's project. Exhaust manifold gaskets. Oh boy