1965 C-10 rearend width backing plate ==> backing plate

[ChrisAunchman]

Hey,
I'm looking for rearend possibilities for my truck. At first I was going to use the one I have from a '78 C-10. I wasn't to concerned about installing new perches. After reading it appears it is a bit wider than what a stock '65 is though.

I have been searching around for the exact dimensions of what came through on these trucks. I read they a 60.5" width. Is the correct width flange to flange? OR WMS to WMS? What are the correct measurements? I have been thinking about a 9" donor instead of the 12-bolt.

Thanks,
Chris

[Captainfab]

The width of a C10 12 bolt from '63 to early '70 is 62" WMS to WMS. From late '70 thru '87 the width increased to 63.5" WMS to WMS. The 12 bolt truck differential can hold up to a lot of hp/tq when built right. To fit a 9" under your truck, you will likely need to have a housing narrowed.

Originally Posted by ChrisAunchman

Hey,
I'm looking for rearend possibilities for my truck. At first I was going to use the one I have from a '78 C-10. I wasn't to concerned about installing new perches. After reading it appears it is a bit wider than what a stock '65 is though.

I have been searching around for the exact dimensions of what came through on these trucks. I read they a 60.5" width. Is the correct width flange to flange? OR WMS to WMS? What are the correct measurements? I have been thinking about a 9" donor instead of the 12-bolt.

Thanks,
Chris

[ChrisAunchman]

What is the width of the drums on a stock 1965 12-bolt. Does anyone know the backing plate-to-backing plate measurement.

Also does anyone know the centers on each axle perch? This way if I do have to weld new perches on at least I have the measurement. Where is the best place to buy the perches?

[Captainfab]

That depends on where on the backing plate you are measuring. Since the backing plates are not flat, that leaves room for inconsistency in measurements. A '65 12 bolt will have 2" wide brake shoes. If you are working with a 12 bolt or a 8.5 10 bolt, and mounting it to trailing arms, you can find the mounts at CPP and ECE.

Originally Posted by ChrisAunchman

What is the width of the drums on a stock 1965 12-bolt. Does anyone know the backing plate-to-backing plate measurement.

Also does anyone know the centers on each axle perch? This way if I do have to weld new perches on at least I have the measurement. Where is the best place to buy the perches?

[krazy_texan]

i just bolted up a 12 bolt in my 65 that came out of a 68 or 69 i didnt measure it but was told it was a directo bolt in and it was and with tires on it looks and fits just fine

[ChrisAunchman]

Well when I say backing-plate I really mean flange. This would be where the backing-plate mounts to the axle housing. That is good to know though that the drums are only 2" wide I thought they were 2.5" drums. I did find a rear out of a 1966, it has either 4.10s or 4.11's. They guy is asking $200 for it complete. I gotta figure on what the frieght is going tobe. It seems like a good price. I'm wondeirng though if I should go narrower since I plan on running a pretty wide rear tires. I know if I found a rear out of an early Ford full size I'd be a little shorter I think.....

[Captainfab]

There are plenty of guys running wide tires with the stock 62" wide rear end. You just need wheels with the right backspacing to make it work.

Just a FYI. When you start measuring rear ends from backing plate to backing plate, or backing plate flange to backing plate flange, you are not going to get the same WMS to WMS because of the different brake widths. Especially when you start comparing different makes of rear ends, ie: GM truck 12 bolt versus Ford 9 inch. The WMS to WMS is what matters, since that is where the wheel attaches.

[bguild]

I know this is a old thread but I know most likely I can get the answer. My 67 has a 6lug 12bolt flange to flange I believe is 57inches. This is the narrower of the two correct? I also need new axles that can be switched to 5x120 z06 pattern. Also I plan to run 500-600hp so who is the best company to talk to?

[Captainfab]

The '63 to early '70 truck 12 bolts are all 62" wide. I've had good luck with axles from Moser.

[bguild]

Is that 62 in from where the brakes are.? I have already pulled the brakes and axles. So I am measurring the four hole plate that is on the end of the axle housing.

[Captainfab]

The 62" measurement is the WMS to WMS. If you are measuring the outside to outside of the backing plate flanges, with the backing plates removed, that measurement should be close to 57"

[bguild]

Thanks!