The Stovebolt Site Forums The Shop Area Driveline GMC RearEnd

I saw a 57 Gmc 1/2tn.It has a different rear end than a chevy. The truck has a v8 and hydra matic transmission. The rear end looks like a Dana,could this possibly be a factory rear. It looks like it was always in the truck. Any ideas,thoughts.

All of the GMC's I have seen have the Dana.

The most common rear in a 57 would have been the corporate rear which was 3.90. The third member will bolt right into a 54 and earlier torque tube banjo housing. An option could have been a Spicer 45 at 3.92 or a V8 with an automatic could have been a spicer 45 at 3.07. The Spicers have the carrier built into the banjo housing instead of a removable 3rd member and more closely resemble more modern rears.

I would imagine that it would interchange with a chevy,The 3.07 gear would be nice to have on highway.

I have a '65 GMC pickup rear in my '57 3200 and it's a Dana 44. If that's what you have in yours, parts are readily available and there are an assortment of gear choices. I just recently had a 3.54 and posi in mine. Only problem is that I'm having difficulty in finding brake drums for it.

Although the Spicer may have been standard, that doesn't mean that many of them were specced with them. Tubeless tires were also standard in 1957, but most people opted for a tube required tires. Corporate rears are much more plentiful in Blue Chip series than Spicer rears.

I used the 3.07 from a '59 GMC in my '56 Chevy. I had trouble finding good brake drums. The Chevy spec shoes, cylinders etc will work but drums won't interchange. Also had to move the tab for the brake hose from one side to the other.