replacement rear end

[oldgoat16]

Hey Guys, question, what rear ends are available to fit under a 55 hardtop? posi's would be the piece i would like.... is there a bolt in available from another GM car, .. I know the aftermarket has a few bolt in's available , but I would like to stay on a budget as this moves along, upgrades later..thanks mike

[BAM55]

A 10 bolt from a 71-81 camaro or firebird is a nice choice. You may have to weld on new axle perches and pinion angle is important but its pretty easy to install cars or truck with leaf spring suspensions. For my truck I bought my 10 bolt posi, with disc brakes for 150 bucks a while back. Mine came with 3:42 gears. The 10 bolt came in many GM cars in the 70's.

[Rick_L]

The problem with a 71-81 Camaro axle is that it's a bit wider than a stock axle. This does not lend itself to the wide tires that many like to use, there are some limitations and planning required.

One important distinction is that the 71-81 Camaro axle is what's called an 8.5" 10-bolt. There are many other "10 bolt" axle types, even the original is a "10 bolt".

There is only one "bolt in" axle replacement for a 55-57 Chevy. That's a 57 Pontiac. Everything else is going to require new spring perches to be welded to the housing.

[oldgoat16]

thank you guys, 57 Pontiac will be a hard find for sure, arizona junk yard...can't think of the name off hand, has tons of full size pontiacs, but good to know, how about a manufacturer that has 9" ford rears that are a decent fit? or some one out there that has a rear end for sale already set up, looking more for a highway gear as it has a munice 4 speed

[chevynut]

There is only one "bolt in" axle replacement for a 55-57 Chevy. That's a 57 Pontiac. Everything else is going to require new spring perches to be welded to the housing.

Not sure I believe that. I thought 67-69 Camaro housings were a bolt-in. I had a friend who installed one in a '57, and to my knowledge he didn't move the spring perches.

There's a bunch of aftermarket rears available.

As for the wider rear, I don't see it as that big of a problem depending on the tires you plan to run. You may need to get wheels with more offset to make them work.

[Rick_L]

Not sure I believe that.

You should.

Been there, but the opposite way. I had a Pontiac rear (not a 57) in my first 55. Pulled it out and put it in a 67 Camaro. I had to put perches on it to fit in the 55 and again in the Camaro.

The other thing about it is that Camaro and Chevy II leaf spring perches are quite different from 55-57 perches, even if they were in the right place you'd have to replace them. For starters the springs are different widths. The other thing is that the Camaro/Chevy II mounts don't even use U bolts.

[chevynut]

Now that you mention it, I think we had this exact discussion once before years ago. I found a source that says the 1st gen camaro spring perches are 42 7/16" on center. The tri5 springs are 46" on center.

[markm]

You should.

Been there, but the opposite way. I had a Pontiac rear (not a 57) in my first 55. Pulled it out and put it in a 67 Camaro. I had to put perches on it to fit in the 55 and again in the Camaro.

The other thing about it is that Camaro and Chevy II leaf spring perches are quite different from 55-57 perches, even if they were in the right place you'd have to replace them. For starters the springs are different widths. The other thing is that the Camaro/Chevy II mounts don't even use U bolts.

I just had a flash back to the 70s ans a buddies 1967 RS [realslow] Camaro with airshocks and N50-15s with a 4 speed and wheelhop and sheared T bolts. I went home and ordered traction bars and replaced the T bolts with U bolts, In the 70s Camaros GM half fixed the problem using one U bolt on each side with a pair of T bolts.

[oldgoat16]

thanks guys, I'm still not sure which way to go, what about a posi center section for a 55 rear end, readily available?, or swap meet piece?

[JT56]

PM sent. I have a 55-64 posi unit and a 57 Pontiac that came out of a 57 BelAir with springs in the stock position.