1970 Gmc 2500

[mems]

I am trying to upgrade the rear on a 1970 gmc. I want to upgrade to something new enough that I dont have to search for brakes everytime I want them but am having trouble finding out what else would fit up under there.

1970 Gmc Pickup
single rear wheel
2 wheel drive

[davepl]

I gave a 1970 GMC 2500. What are you having trouble finding? The only thing I had trouble with was brake drums themselves. Mine's the Dana 60, which I assume yours is too.

You could swap in a 14-bolt corporate. If I recall correctly you have to move the spring perches but otherwise it fits.

[mems]

Yeah, the drums are the issue. Have you had any luck finding drums anywhere? Every single place I try sends me the wrong ones and it takes two weeks to get those

[davepl]

No, I had mine turned and I'm worried about next time, like you.

RockAuto does list a number of rear drums for the C2500, but how do we know which is the right one (if any)?

[ElKotze]

I wrote down the number on the drum, went to NAPA and got the right one. My '72 C20 has a Dana 60. My '69 had a HO72, parts are impossible to find, so I put a 14 bolt SF in it. I had to move spring perches and shock mounts, not a big deal. Pushes the rear wheels out a little, too, which I like. If you get a 14 bolt, try getting a Full Floater. Best axle GM ever built, imho, and all the gears you'll ever need.

[El Dorado Jim]

get a 14 bolt full floater from a 73 or newer truck, move spring perches and shock mounts and you will be good to go

[BILT4ME]

I took measurements on the rear drums of our 70 GMC K2500 (4x4) as well as the measurements on a rear axle assembly I bought from a 72 Chevrolet 2WD (leaf spring) and dimensionally, they were identical. Both are Dana 60 with 4:10 gearing and leaf springs and drum brakes. I actually used the axle shafts from the 2WD unit in our 4WD unit because they were less worn.

I measured ID
Brake width
back-spacing from inside of drum to frthest point on brake area
back-spacing from inside of drum to farthest point of drum

I discovered (3) part numbers were within tolerance of each other. Each one was updated throughout the years.

I looked up the part numbers stamped into the face of the drum and had (3) different numbers. I then used the RockAuto site to find and cross-reference part numbers based on what I knew.

I bought drum P/N Centric 12366039 and Brake Shoe P/N Centric 11204190 They fit perfect.

Start on RockAuto with your APPLICATION and find the parts as listed. If you can't find that, then scrape off the rust on your existing drums and find the part number stamped in the face of the outside of the drum (where the wheel mounts) and Google from there.

I do searches through:
Rock Auto
O'Reilly
NAPA Online
General Google stuff
Summit Racing

I may find a tidbit in many or each in order to confirm a whole part. I usually try to confirm the data from at least two sources. Then it's still a gamble, but less of one.

Good Luck!