[chaz069]

The rear end in my 67 is clunking. End of my Woodward Dream Cruise weekend. It has casting numbers in the center housing of F057 9782977 Pontiac nos. I have a spare out of a 67 Lemans 0316 9783393. Appears that the only difference is in the coil spring mounts on the axle tubes. The in car axle has raised mounts to accept the coil and hold it in place while the other has a flat surface for its spring mount. I have had absolutely no luck in finding any numbers stamped into any part of the tubes. The u joints use a horseshoe type clamp with nuts to hold them in place. I am assuming this is an 8.2, but what ratio? Done a lot of looking without any definitive identification. Any and all help would be appreciated. Thanks chaz069. My 80 T/A in for paint and a major rebuild. Now the 67 Goat.

[Jeff Hamlin]

'66 is the flat perch which uses a bolt down/on retainer.
'67 has the hump to hold the spring in-place.
The '66 will bolt-in but is 1" less in width.
To ID just pull the cover and look at the RG #s

[chaz069]

Are the parts interchangeable? Such as Axles,gear carrier,etc. The 67 housing, backing plates and brake assy are in better condition than my donor axle assy. Thanks chaz069

[Jeff Hamlin]

Everything should swap 10 bolt to 10 bolt no problems I recall.

[chaz069]

Thanks . I will start measuring. Chaz069

[Cammer-6]

you will spend more transferring parts over than if you had just fixed the clunk
if the rear is a posi just add 2 bottles of GM posi additive

[400 4spd.]

i think the axles were shorter in the 66-back rears. Probably 1/2", because of the 1" total difference in rear ends. At least the axle I pulled from 65 was shorter than the one from my 67. It worked fine though.

[Jeff Hamlin]

If your just swapping the rear, all you need to do is unbolt the axle retainers,
Pull the axles and use wire to suspend the brake/backing plates with all parts left in place.
Pull the lower and upper arm bolts only at the rear and let the arms stay in-place.
This way you just slip out the old rear then in with the replacement rear and you never have to disconnect/bleed down the brakes.
I swapped 3 rears into my '66 one day all within 4-5hrs just to try different geared/rears I had at my disposal.

This keeps all the good brake parts on your car.

[GT182]

Valvoline has 85W-140 rear gear oil with the Limited Slip additive already in it. Works great in my 2000 Jeep GC. I'll be using it too when I get a posi unit installed in the GTO.

The Jeep has always had a howling noise in the rear when you'd let off on the gas since we bought it. Agravating to say the least. Checked out by two different dealers back in 2004 while under the warranty and they found nothing wrong. Ha! Changed out a pinion seal this Spring and used 85W-140 in the rear end. No noise at all now.

[400 4spd.]

Originally Posted by Jeff Hamlin

If your just swapping the rear, all you need to do is unbolt the axle retainers,
Pull the axles and use wire to suspend the brake/backing plates with all parts left in place.
Pull the lower and upper arm bolts only at the rear and let the arms stay in-place.
This way you just slip out the old rear then in with the replacement rear and you never have to disconnect/bleed down the brakes.
I swapped 3 rears into my '66 one day all within 4-5hrs just to try different geared/rears I had at my disposal.

This keeps all the good brake parts on your car.

That is slick!

[Mister Pontiac]

Originally Posted by 400 4spd.

i think the axles were shorter in the 66-back rears.

Correct. Just use the respective axles with the respective rears, and the everything else swaps just fine (backing plates, brakes, etc...) aside from the spring perch mounts being different.

Hope that helps!

[chaz069]

Thanks again for all the info. Worn carrier and pin, elongated and well worn, low rear end dope, forgot to check. Unknown if axle bearings are also worn, low fluid. Leaking pinion seal. It has a 2.78 open carrier in car, donor axle is a 2.56. Unknown mileage on both rear ends, but 37 years old. Also they are both 8.2's Spider gears worn and sloppy also.I am running a 75 455 with a built 350 with a shift kit. Just a cruiser with a little oomph. Thinking about a complete axle assy change, but bolt in. Ha Ha! any suggestions chaz069

[chaz069]

Just a note on rear end identification. Forget the tubes. NO Numbers. Open her up and read the numbers on the ring gear. Look in the book. (Your assembly manual) and you have positive ID. There is a lot of misinformation regarding the location of GM numbers and what they mean. If its tagged it's a posi. I just spent the better part of the day and some, looking for the location of the numbers to no avail. chaz069

[merlotgoat]

Took me a long time to find the number stamped on my tube. It was very faint and I only discovered it by accident ( I had given up trying to find it) due to momentary glare from the trouble light.