rear end question

[straycat990]

Did the 1979 turbo sport coupe cars come with a 8.5" rear?

David Morgan

 

[buick83-T]

rear end

The 79 came with the 7.5 rear. Was'nt until 84 when they went to the 8.5 rear.

 

[straycat990]

thanks for the answer .. found a 79 for sale in the local paper .. was just wondering if it was worth while for the parts.

 

[BiGBoY]

Is it possible to put an 8.5 at the place of the 7.5 or it's better to change all the axle?

 

[BiGBoY]

don't anwser, I've seen the differences between the two diff on a web site. Sorry!

 

[REDS HOT AIR]

I seen that car too

I posted in before black section asking if it was worth anything and got no reply ..


we'll have to meet one of these days..


are you the guy who use to work at york tranny with Mark Jenkins with the tubbed ranger?

 

[Ttype83]

REDS, Sorry I didn't see the post, been pretty busy lately.

How much can you get for it??? Not much. If you intend to use it as a daily driver and has low miles, go for it. How much would you spend on a daily driver with low miles..that's how much it's worth.
HTH

Jim

Or you can check pat's post, he listed afew 78 & 79's...Hands off the Green one, I need that one to embarrass my kids

 

[fc227]

Yes, It is possible to change from the 7.5" to the 8.5" rear end, But you will have to get the 1" shorter driveshaft. I have done this in my olds.

 

[BiGBoY]

No I don't work there (if you were talking to me REDS HOT AIR) sorry.

Okay for the 8.5 tranny. But is it possible to find a good 8.5 axle anywhere out of 442, H/O, and GN from 80s since there's only a few available (if I can say no available) in junkyard?

 

[b4black]

You won't find them in a junkyard. They are around, but expect to pay ~$350 for an open, ~$700 for a limited slip.

Unless your running in the 13's (like Fred ), stick with the 7.5" for the money. You should be able to get a 3.42 or 3.73 limited slip 7.5" from a Monte Carlo SS for under $300.

 

[fc227]

I was running low 13's on the 7 5/8" rearend. However, it was always in the back of my mind that that was the weak link. The 7.5 /7 5/8" is lighter than the 8.5" also. Less unsprun weight. I ran in the 14's for years on the auburn 7 5/8 carrier with "0" problems.

 

[turbofish38]

Just to add my $.02. The 4th generation F-bodies are still running the 7.625(the old 7.5) and they have 320 HP available. The only difference is 28 spline axles on the F and 26 spiline on the A/G. Assuming thats not the weak link than a 7.5 should be sufficiant at your current power level. Besides I've always heard auto transmissions were kind to rear ends. As compared to dropping the clutch at redline.

 

[BiGBoY]

Just for fun, is it that hard to put 28 or 30 spline at the place of 26 and how much the axles will be improved with that mod?

 

[turbofish38]

Yeah pretty hard. You would have to go to a set of custom axles to get 28's into the G-body. One thing I forgot. Another weak link might be the posi cases themselves. The old 7.5 was made by Borg-Warner and was a cone style posi like the old GS's used. And the newer ones are Auburn styles with the disc type. I stripped the teeth off a B-W with my ElCamino running a 150 HP 305. But it was a high mileage unit so who knows how long it would last with some real power in front of it. I'm not sure but I think you can find the Auburn case in a middle 80's S-10. I dont remember what year they went to 28 spline but some of those trucks have 3 series gears in them.