Nasty455

My rear end looks twisted...another buddy commented the setup looks like 73 and newer...not 71 as is the rest of my a body.
It's a 10 bolt..possibly from a chevy???
Anyone have this type of setup???
Thanks.

Nasty455

Nasty455

Nasty455

Doc350s

Looks like a 10 bolt. The shocks are not mounted in the correct location, looks like a beefier sway bar and it would appear that somebody ground off the rear side of the spring mounting pad. Brake line normally runs below the pad mount.

IMG_0917.jpg

copper128

It does have the 73-up style sway bar and lower control arms.

507OLDS

That is a 73-up style that they cobbled into a 64-72.Not correct.Those perches you see hanging in the front are the shock mounts.The springs are cocked because the 73-up have the spring perches over the axle tube whereas the 64-72 have them in front of the tube.

monzaz

Yep 1973-1977 A-body GM 10 bolt 8.5 rear.

BOY oh Boy...Is that the way they had the springs in there??? !!! WOOF. Not cool.

The rear will be an 1" wider over all too among the spring perches, Upper control arms mounting points wider and loweron the center section and shock mount trouble too.

73-77 rears are all by them selves... Sorry to hear....

Nasty455

That's Ok...probably why the car was so cheap.
The goof who sold it to me welded in f body engine mounts..rather than bolting in correct Chevelle mounts..if he was running a Chevy motor.
The car is in overall good condition.
I plan on running a 350/350 setup with a big cam...I could use some 4.11's.
I've never had rear end problems...so this will be a good experience.
I believe the rear end is a 308 Posi...as I marked the drive shaft and rotated the wheels counting the turns of the pinion.
Is 3.08 a Chevy axle ratio for 73?
Thanks guys for the help.

Nasty455

Rickman48

Is it my imagination, or is that housing twisted up in the front??
Can't imagine the u-joint angle being anywhere close to correct, if that's the case!
Get some to put in the trunk - for road breakdowns, if you're driving it!

Nasty455

I doubt the housing is twisted...if it is,it's twisted in the wrong direction...he swapped in an incorrect rear end.
The 1973-1977 rears are different...they have staggard shocks...I believe the earlier setup does not.
Anyone has restoration photos of 68-72 to show me the correct setup?
Thanks.

Rickman48

By 'twisted', I meant too high in the front - pinion angle is supposed to be the same as the driveshaft.
Maybe upper or lower control arms are too long/short, but something's off!!

monzaz

Upper control arms are too long . Pushing the top back and the pinion angle too far up at a 45 degree angle in the from. You will eat plenty u-joints if driving that way. There are plenty of rears still out there that will fit that car.
anything from 1965-1972 chevelle skylark cutlass gto lemans el Camino Monte carlo

Jim

Nasty455

Thanks guys.
I have a few rear ends laying about...but they are all from F bodies.
Time to hunt down a decent replacement.\
Another big project to fill my time.

Nasty455

I got the rear end removed today.
The code on the rear end is yz-1977 308 posi.
Any ideas what vehicle it came out of?
Malibu wagon?
I took off the cover,and removed the lubricant and had a look see.
pretty clean inside...not much of anything besides fluid.
whats the best way to clean the posi unit before refilling and adding a new cover?
Thanks.

MrRocket

3:08 is Olds gears for the 73-77 Hurst or 442 I believe.

Nasty455

I believe it's a Chevy 10 bolt.
I'm unsure if the rear control arms are originally from the 68-72 or the 73-77 donor.
I'll have a better idea once my 74 Elky arrives and I can compare the length of it's stock components.
This rear will be a spare for the Elky..unless it also has a posi.
I'll will be buying a correct rear end 68-72 for this car.
One rear control arm has a spot rusted through so I will be either be buying new boxed stuff or reusing what the Elky has.
I might as well replace everything while it's out,but The $500 could be spent elsewhere.

monzaz

You would need to remove the unit and disassemble to clean and inspect properly. The thing is probably good just clean out the bottom of the case of the housing and fill her back up. IF you are going to attempt to drive it just change the oil again after about 100 miles of good turning and road coarse driving and that will flush the old fluid out for you. JIm

Nasty455

I transplanted the 308 posi into my El Camino and discovered the problem.
Here is what the rear end spring perch looks like on the original.I need to remove these perches and have them welded correctly to the new rear end.
The other joker welded them too far forward rather than centered over the axle tube.

Nasty455

I'll have to guess what it came out of,when ordering brake parts.
I'm ordering a few cheap 77 Monte Carlo brake parts to see if they match what I have.
Fingers crossed.