VinR1

iTrader: (17)

Fwiw I have a '93 auto, stock stall, stock gears, bone stock. I do not, nor do I ever plan to race. I have no desire and my car has not been north of 4k rpm since I bought it.

That said, I'm picking up a non-posi 3rd Gen rear for practically free. My plan is to use the narrower rear with some super low offset, deep dish wheels.

Will my 4th Gen posi, gears, brakes, etc swap over? I don't have traction control and will be deleting abs. And, I will let a professional do the swap/install with all new seals, bearings, shims, etc. I plan to keep a pair of 2in adapter/spacers on hand in case I want to use my factory wheels or spare.

Is this doable and what should I look out for?

JRENIGAR

iTrader: (37)

Its my understanding that the 10 bolt rearends are exactly the same except the splines on the axles are 26 on the third gens instead of 28 like the fourth gens. I do know however that there are a certain # of third gens that had an optional borg warner 8in diff in them but I think they are also a drop in conv but not sure on that one.

89 formula350

iTrader: (8)

yes it will fit. yes no abs. the rear is narrower by about 1.5 or so on each end. 4th gen brakes will bolt right up. the early thirdgens had 26 spline the later years were 28

the thirdgen also had a Borg Warner "9 bolt" it was a 7.75" ring gear and is stronger than the 10bolt by a fair amount most are worn enough by now that you wont notice any improvement in strength with out properly going through the posi and bearings

or if your lucky some got the GMPP dana 44

VinR1

iTrader: (17)

cool, thats what I wanted to hear

I dont mind if its not any stronger, it'll give me some hands-on experience with rear ends and allow me to run lower offset wheels

xtreme2001

i run a 3rd gen in mine with 28 spline axles and the torsen carrier

VinR1

iTrader: (17)

got the rear - in my garage on stands now. its out of a '91 V6 firebird

any idea what # spline axles this should have? AFAIK its bone stock internally. I'm guessing my '93 has 28 spline axles? my plan is to move my posi and gears over to use with the 3rd gen rear

ALSO, it has the Delco calipers with new pads and very good discs... any idea what that setup is worth since I'll be moving my LT1 brakes over??

TIA

xtreme2001

should be 28 spline......no idea on what the thirdgen brake setup would be worth

JRENIGAR

iTrader: (37)

I have personally seen that borg warner rear in action and it seems strong. Friend of mine has a 86 camaro with built 383 heads cam in a 5 speed car with 200 shot on mickey dr's. It's seen 5000rpm launches running deep in the 10's at the track with his car. Coincedence? You be the judge. He runs the **** outta this car and has probably 30'000 miles of hard driving on this rear and it was used from another car before his but I dont know how it was treated before he got the rear.

89 formula350

iTrader: (8)

I think those rear are very strong for a 7.75" ring gear! its the same rear as the TTA its also what I was using on my ls1 t56 car and MT slicks at the track it took the abuse but I knew it was on borrowed time. do they break hell yeah but for such a small gear its one tough little guy and its setup very nice looks like a small dana, no c-clip junk and 4 pinion posi


For the brakes IDK I would look on TGO if its a 91 3.1 rear it should be 28 spline but I thought drum brakes.... 88 1/2 -up got the PBR calipers I'm thinking you will have to open it up and see what is really in that one

VinR1

iTrader: (17)

its never been opened up and I know for a fact it came out of a '91. I assume my '93's posi and gears will work with those axles?

the brakes are different though - the previous owner of the rear took off the drums and converted to a complete Delco disc brake system

xtreme2001

the guts from your 93 will work