New Poster with Differential ID question

[swiftwater15]

I'm restoring my grandads '72 Fleetside, the truck I learned to drive in. I'm trying to Id the rear axle. It was a ranch truck with 64k original miles, but most of them at about 10 mph bouncing around the dirt roads.

12 bolts holding the rear cover. "GM60" cast into the front driver's side of the casting. "NF3896838" cast into the passenger side casting. Five bolt axles, with 16" rims and heavy spring options.

If this a Dana 60, GM 12 bolt or . . .?

Thanks in advance. Tried a search and didn't find an answer.

Dan

[kwmech]

1/2 ton? 3/4 ton. A Dana 60 cover will have 10 bolts. 12 bolt will have 12 bolts

[Longhorn Man]

a GM 12 bolt. It's a 1/2 ton truck.

[DANTIP]

If you want more information about the gear set, you can look for the axle tube stamp as shown in the sketch (don't pay attention to the casting numbers on the sketch, I borrowed them from a Camaro or Chevelle web site). The stamped code will have the axle code and a coded plant and build date. If you find the stamped code, post it and someone will look it up for you.