hotrod87camaro

how much trouble is it to put a 12 bolt rearend in a thirdgen? i know someone that has one i could probably get cheaper than buying a posi unit and gears. has anyone here done this? what all would be involved?

AlkyIROC

Since the third gen never came with a 12 bolt, there are no factory 12 bolts that are a direct bolt in. Because of the third gen torque arm suspension, swapping in a junkyard 12 bolt isn't very easy since there's no strong way of attaching a torque arm mount to the cast iron center section of the 12 bolt. The only factory 12 bolt narrow enough to fit under a third gen is from a first gen.

A complete aftermarket direct bolt in 12 bolt for a third gen is around $2500

hotrod87camaro

i didn't expect it to be a direct bolt in, i was just wondering if it was even possible and what all i would have to do. i think the rearend is actually from a 69 Camaro. would there be any way to attach a torque arm to it? basically, can i make it work or would i be better off to just get gears and a posi for my stock 10 bolt?

AlkyIROC

Using the factory suspension system, converting the diff could cost you more than the cost of a new diff.

As I already mentioned, the 12 bolt center section is cast iron. To fabricate a mount so that the torque arm could attach to it, you need to do some engineering for proper position plus you'll need to weld the mount or mounting plates onto the cast iron housing. The proper way to get a good weld on cast iron is to heat it up with a torch until it gets red hot before welding to it. Although this isn't a problem for any welder, the problem you'll probably get after any kind of welding onto the housing is warping. If the pinion bearings or side bearings go out of alignment, I don't think there's any way to fix it.

Personally, I'd stay away from trying to adapt a factory 12 bolt to a third gen unless you plan on changing the rear suspension to ladder bars or a 4 link system. It's a lot easier to adapt a 9".

hotrod87camaro

somebody told me they thought there was a kit or something? kind of like the torque arm relocation kit for a turbo 350. has anyone ever heard of this before?? i could probably get it a lot cheaper than buying a posi unit for mine, and i'm sure it would be a big upgrade from my current 10 bolt so i was just hoping there was a way to do it.

AlkyIROC

The torque arm relocation bracket is for a transmission swap not a diff swap.

89gta383

iTrader: (5)

You are probably thinking of the south side machine ladder bar set-up which replaces the torque arm, it is sold as a 'kit'. Check summit racing.

hotrod87camaro

i know that, i'm not retarded, i was thinking they might make a bracket for that too, like a similar ideal but for the rearend rather than the transmission. i know its different.

AlkyIROC

You can buy a torque arm mounting bracket for a 9" from Currie but nobody want's to risk selling something like that for a 12 bolt because it would need to be welded to cast iron. A bolt in 12 bolt has a mounting area cast into the housing.