OK so I am sick of the 4.10's (chev 12 bolt) that my car is equipped with currently. They were great when I had a built 464ci and 200-4r with all the billet goodies, but not so good with a stock '70 455 and TH350. I have been searching high and low, trying to find a better rear locally. The only thing I have found was a rear out of a '70 Cutlass. It's the odd-ball with the 12 bolt cover and 10 bolt ring gear. It's a 2.56 open. The guy wants $275 for it, and $50 for the driveshaft. Attached are pics of the rear still in the car : Before I spend any $$, does anyone know if the driveshaft length for the olds rear, and the stock rear is the same? I originally had a 10 bolt in the car, and swapped to a Ch*vy 12 Bolt and the same driveshaft worked just fine. I didn't know if the axle centerline to yoke centerline was different on this olds rear. What I was really hoping to find was a 10 bolt with 2.93 posi..... My trans is set up for 2.73 gears (I'm referring to the speedo gears), but I'm running 28" tall tires, so 2.93's would be virtually the same ratio as stock. I'm really just trying to get my buick to be more driveable and not spend a small fortune on a rear. I'm not looking for a killer fast car, I just want to enjoy what I have, and be able to drive it anywhere!!
Don't waste your money on the 12 bolt Olds.....get a corporate 8.5" from a 71-2 Skylark/Cutlass...much cheaper to build and maintain. Contact Monzaz...he should have some....I will be bringing him some in July.
I just removed one of these from my 72 and the drive shaft is 48 1/2" from center of ujoint cap to center of ujoint cap. This was set up with a TH400 tranny. He's right though get an 8.5 I just got new posi, 3.42 gears and install kit for $400.00 shipped to my door. That ain't gonna happen with your OLDS rear.
There is a 4x4 shop 1/4 mile up the road from me, I asked them about re-gearing my 12 bolt, and to get a 3 series carrier and gears, plus install, he was talking about $700.... I'm not really looking to spend that kind of $. I honestly didn't expect it to be this difficult to find a 10 bolt axle, these parts must really be drying up! Seems like a few years ago, 10 bolts were dime-a-dozen for 2.xx rears.....