Author Topic: Replacing rear housing  (Read 13473 times)

dab67

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Replacing rear housing
« on: July 12, 2006, 06:05:59 PM »
Has anyone ever attempted to change just the rear end "cabbage head" to convert a rear end from a 10 bolt to a 12 bolt? Is this even possible or is there more to it than that? I know you have to remove the axles , shafts and the splines and every thing else. But would all these parts from a 10 bolt match up to the 12 bolt cabbage head and would the time effort be worth it compared to switching out the 10 for a complete 12?

dab67

hotrod68

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Re: Replacing rear housing
« Reply #1 on: July 13, 2006, 04:49:02 AM »
what is a "cabbage head?" Sounds like you're talking about an old pre-Spicer axle with a "hogshead" chuckle. The Camaro 10 and 12-bolts didn't have "cabbage heads" or 'hogsheads"--they had an inspection plate and the guts didn't come out from the front. The only things I know that will interchange from a 10-bolt to a 12-bolt are the brake backing plates.
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dab67

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Re: Replacing rear housing
« Reply #2 on: July 13, 2006, 11:45:33 PM »
hotrod:

I am referring to the housing that holds the rear end gears. Back in the"day", it was sometimes referred to as the cabbage head  because that is was it resembles, but I'm guessing because you never heard the saying you are not from my generation.  :D

dab67

lakeholme

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Re: Replacing rear housing
« Reply #3 on: July 14, 2006, 08:50:38 AM »
Well, I'm old enough to remember...  Cabbage head and also a couple of politically incorrect names.
Are you just considering a cosmetic change; i.e., 12 bolt look but all 10 bolt stuff including the gear assembly?
I'm really not sure any of it would work.  It might fit, but what would you gain?
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dab67

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Re: Replacing rear housing
« Reply #4 on: July 14, 2006, 11:07:08 AM »
HEY PHILLIP:

I don't if any of the "inners" from a 10 would fit a 12 either, I doubt it, but wasn't sure if everything else could be used like the axles and axle housing. With the cost of replacing a 10 with a 12 or visa versa, thought maybe it would be a little less expensive if you could swap out the 10 housing and gears with a 12 housing and gears and attach everythign else. I guess you could call this an off the wall kind of question.

Dave

JohnZ

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Re: Replacing rear housing
« Reply #5 on: July 14, 2006, 03:15:12 PM »
There's no replaceable "housing" on any post-'64 GM 10-bolt or 12-bolt axles; the only removable part is the stamped sheet metal rear cover, and none of the internal parts interchange. We used to call it the "pumpkin" on C1 Corvettes and '64 and earlier passenger cars when the front of the axle housing that contained the gears and diff was a separate casting that bolted to the "banjo" (axle housing), like a Ford 9-inch axle.
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hotrod68

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Re: Replacing rear housing
« Reply #6 on: July 16, 2006, 06:18:06 AM »
Dab--I meant no offense--I don't know what your generation is, but I'm 48 and in "my day" we called them hogsheads, at least around here. Pumpkin is also a familiar term, and as Lake implied, there were a few other words for them you can't say in polite company! But they were the old '64-back Chevy 10-bolts without an inspection plate, and Camaros never had them. I know--my 1st car was a '64 Impala and that ^$#@% hogshead shelled spider gears like clockwork. Just didn't get why you'd want to put one under a Camaro.
HotRod'68  1968 SS350 coupe undergoing frame-off resto/rod. 386/350/4.11s
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lakeholme

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Re: Replacing rear housing
« Reply #7 on: July 16, 2006, 03:34:14 PM »
Man, you guys are taking me back!
Actually, I think its great when we share "terminology".
It's also very helpful to know what is interchangable and what's not.
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dab67

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Re: Replacing rear housing
« Reply #8 on: July 19, 2006, 05:01:10 PM »
Hotrod:

No offense taken, I'm to old for that!!!!!!!! I got you by about 10 years, but at my age who counts! Generations have always had their own verbage for the cars they drove and the parts on them. Lake is correct, it is great to share it all again and "step back in time" and to learn what others know.

Dave

dans67camaro

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Re: Replacing rear housing
« Reply #9 on: March 12, 2007, 02:42:42 PM »
Since I worked for the GM axle plants iin product engineering in the mid to late 80's and  in 94 for AAM when they were seperated from GM, I should know the answer to this question. I believe the 12 bolt axles have a larger ring gear (8-7/8) vs 8-1/2 for the 10 bolt design. There could also be a different hypoid offset. Also, the axle shaft splines into the side gears are likely different. Don't remember about the wheel bearings into the housing or the fit onto the axle shafts. So, in a nut shell, not interchangeable. In later years, GM got smarter and upgraded the 8-1/2, 10 bolt and eliminated the proliferation of the  12 bolt. Even more recently, the 8-1/2 for passenger vehicles, specifically the F-car went to an  upgraded 7-5/8 rear axle with better steel and heat treat technology. There's no question a 12 bolt is a better (stronger) way to go!