View Full Version : 1965-75 GM Corporate Rear

10-13-2000, 08:01 PM
I'm looking for a 1965-75 GM corporate rear for a 3/4 to 1-ton truck. These are also known as a "GM Pig" or "GM 10-bolt Truck Rear". Single or dual wheel is not important.

Third member should have 411 or 393 gears. The third member drops out of the front of the housing like a Ford 9". The housing has a round center section. Some have a rear cover and others are part of the housing.

Willing to pay $50 to $100 reward if you find one and I purchase it.

Chuck Smith
10-14-2000, 02:17 AM

Never heard of such an axle. Only the GM 14 bolt. When we refer to a GM 10 bolt here, it's the wimpy one.
I know from 73 on, the 3/4 ton models used the GM 14 bolt.
I guess you learn something new everyday. Has anyone here ever heard of this axle Jim is talking about? I don't mean does anyone have one, but has anyone even heard of one?
I know some of the 67 - 72 models used an Eaton rear axle. Like this one here.

<img src="http://www.chuckschevytruckpages.com/images/brettaxle.jpg">

The diff is a full floater and approx 13 inches across. This belongs to a guy with a 71 Chevy, who lives in Austrailia. It's got 10 bolts, but he was told it was an Eaton axle. Is this what you are referring to? Is it in fact a "GM pig"? His has single rear wheels. He is having a VERY hard time getting parts for it in Austrailia.

I'm at a total loss otherwise!


John DiMartino
10-14-2000, 09:42 AM
I too,am baffled.I have never heard of one fo them either,I think maybe he's reffering to the wimpy 10 bolt 8.5?It certainly wouldnt be under a ton or 3/4 though.I thnk he wants a full floating 10.5" 14 bolt,with a locker-he just doesnt know it yet LOL.Street rod Jim-is the rear your looking for a 5,6 or 8 lug?What size brakesare on it?there are different widths of truck rears,depending on if it came from a pickup or cab &chassis-which one are you looking for?what size is the ring gear on this unit?Since i dont think you know what rear your talking about,being more specifc-we can tell you which one you need and what its proper name is.

Chuck Smith
10-14-2000, 12:04 PM
The part that loses me is the "third member". I didn't know GM ever made a 3rd member rear.
Though, looking in my 77 GM Light Duty service manual, they do show a 3rd member type. It has a 12 1/4" ring gear. BUT, it says it has an 11,000 lb. capacity. I know the 14 bolt is rated at 7,000 lbs. I've seen the 12 1/4" in the manual before, but figured it was for step vans, and possibly C/60 models and motorhomes. I sure haven't seen it in a pick up. In fact, I've never seen one, so you will have a really hard time finding one.
Maybe in Hemmings Motor News you'll have more luck? I doubt you'll have any luck in this forum with an axle like that.
You might want to look in classifieds that cater to larger trucks and motorhomes. Maybe it's in C/50's C/60's C/70's and motorhomes. Oh, and it's also a single speed differential. So if you see "split rear" in an ad, it's not what you want.


10-14-2000, 10:44 PM
maybe youre looking for a dana 40 or 60 ...my 67 has a 12 bolt rear loaded. chevy did use dana rear end in some 3/4 and one ton truck very common espeeliy on dual wheel set ups

10-14-2000, 11:24 PM
Probably referring to the Rockwell axles found in some dual wheel apps.

10-16-2000, 07:58 PM
not sure where your located jim, but i found this ad in my local want advertiser,

from full sz Blazer. Basket cases. Gd for rebuild. Rear nds new gears but shafts are OK.
$150/bo for all; Call Paul. (Manchester, NH) 603-647-9369 n

...says 1/2 ton but who knows maybe its the same


Chuck Smith
10-17-2000, 09:32 AM
Nope, those are the 8.5" ring gear axles. He's talking MUCH bigger. Who knows, it may be the 12.5" ring gear shown in my factory service manual.


10-17-2000, 06:12 PM
Chuck has a picture of the rear I have. I'm in northeast US,around here there called stump pulling rears, I,m told GM used them with 3.73 and 4.10 gears in camper specials, there were 3 different carrier's produced, only 1 of these will accept the 3.73 and 4.10 gears