question, G body 7.5 rear life

[Bernhard]

https://gbodyforum.com/threads/86-44...ear-end.79216/
This is not my diff.
I have had good luck sourcing parts from car specific forums.
1500 US seems high but that may be the current rate.

[Lyn Smith]

Isn't a 7.5 rear end the same rear end they put in Vegas in the 70s?

[Monte Howard]

Friend of mine has a 87 Grand National rear end for sale, 3.90 gear TA Cover, stock axles, good drum brakes. He is In Illinois, but will be going to SGMP in a couple weeks for ducks race. He can deliver between Illinois and SGMP $1,600 obo

[Greg Reimer 7376]

Originally Posted by Lyn Smith

Isn't a 7.5 rear end the same rear end they put in Vegas in the 70s?

Man,I hope not! In the 70's when I worked on the line at the Chevy dealer, the Vega had a ring and pinion pitch noise(howl) at about 30-35 MPH. You could adjust pinion depth, experiment with back lash, do whatever you want, but that rear end was going to howl. We were so glad as more and more Vegas went beyond warranty because we knew people weren't going to spend money on a Vega to fix it. We never really came up with a real fix for that unit, it just seemed to be a real poorly machined piece. Quality control was nonexistent anyway on those cars. Also, when the Chevette came out in 1976, every last one you would ever drive had a pitch noise that would come in at 40 MPH. You didn't need the speedometer to tell when you hit 40, the rear axle assembly would tell you. Also, full sized vans did that, too, although trucks wouldn't even though they had the same rear end assembly. Later on, it dawned on some of us that the Vega, the vans and the Chevette all were unit body with the rear end bolted to a unit body. It was possible that setup transmitted a normal noise to the passenger compartment that the separate frame and body with mounting bushings somehow isolated it. I was nervous about smaller rear ends not only from the strength standpoint, but wondered if the noise came from poorly machined or mismatched parts somehow.

[Jerry Terry]

You are right Greg the G Vans were horrible with rear end howling new or used years ago ive had race car rear ends that didnt howl as bad as them. going back to the original question go ahead and buy the good stuff now for a 12 bolt and then no worries.




Jerry
Retired 3490 3492 STK SS SST

[JakeB23]

Where or Who do you guys recommend for a 12 bolt replacement? Moser/Strange? Thinking of ordering a bolt in 12 bolt for a 4th Gen Camaro... I'm thinking it would be best to just order the whole ball of wax at one time..

[Jeff Stout]

Originally Posted by JakeB23

Where or Who do you guys recommend for a 12 bolt replacement? Moser/Strange? Thinking of ordering a bolt in 12 bolt for a 4th Gen Camaro... I'm thinking it would be best to just order the whole ball of wax at one time..

Double check when ordering. We shopped around and told every person that was selling Moser what exactly we wanted. One company was cheaper so we went with them. Come to find out after we received unit some items we requested were not on housing assembly. ( NOT Moser fault)Complained and showed exactly what we told them. They said we paid for what we received. So we had to order the other items to make it 100% ready to bolt in. I think it was no studs, wrong axle bearings, and something else.
It was for a 78 Camaro. Went in car with no problem. Everything fit well.

[nhramnl]

[QUOTE=Jerry Terry;625161]You are right Greg the G Vans were horrible with rear end howling new or used years ago ive had race car rear ends that didnt howl as bad as them. going back to the original question go ahead and buy the good stuff now for a 12 bolt and then no worries.

The G-van rear axle howl was always kinda figured to be attributable to the fact that the operator was driving a huge "speaker" down the road. Or maybe better referred-to as a megaphone. Pickups probably had noise too, but you just couldn't hear it in the cab.

[Greg Reimer 7376]

[QUOTE=nhramnl;625230]

Originally Posted by Jerry Terry

You are right Greg the G Vans were horrible with rear end howling new or used years ago ive had race car rear ends that didnt howl as bad as them. going back to the original question go ahead and buy the good stuff now for a 12 bolt and then no worries.

The G-van rear axle howl was always kinda figured to be attributable to the fact that the operator was driving a huge "speaker" down the road. Or maybe better referred-to as a megaphone. Pickups probably had noise too, but you just couldn't hear it in the cab.

The pick up had a separate body/frame construction so any noises created by a ring and pinion wouldn't have transferred through the body bushings between the frame and the cab. All the cars that were notorious for rear end noise were unit body as well. The van rear end and the truck were the same at that time(mid-late '70's, ) and they held up pretty well, but there could have been a lapse in the quality of the set ups. I don't know how they initially set up rear ends at the factory, but it could have needed some design engineering. My late aunt from decades ago bought a new 64 Nova wagon with a 283, a Glide and power steering and brakes. It was the first year for the 283 in the Nova and the first 10 bolt 8.20 rear end. It had a rear end howl at some speeds as well, and Novas had leaf springs attached to the unit body like the vans did. I don't remember anybody telling me that Chevelles of that era had that problem, but Chevelles always had a full frame. The Nova she had came out about 10 years prior to my entry into the world of car repairs and service. i did wish at one time I had the original block out of that car!!

[jmantle]

This isn't directly related but when I built the Pacer I put a V8 AMC 20 rear end in it, 8 7/8 ring gear. Thinking putting the original 6 cylinder rear end in it would pick it up, I put together an AMC 15 (Dana 35) with the 7 9/16 ring gear. Results were I didn't see any improvement in the et. I haven't broken the Dana 35 but I didn't see any gain. Same ratio in both cases.

Jim Mantle V/SA 6632