[taz3]

Will a 4th gen 8.5 10 bolt right into a 3rd gen?

 

[Baddbob]

I think the overall width and width between the spring perches is wider on the 4th generation.

 

[taz3]

I found a 75-77 not sure, but it has a posi 8.5 in it, I might be able to buy cheap. The car rotted real bad from sitting. I'll have to measure them.

 

[tnblkc230wz]

Check Novaresource.org. They should interchange. All 75 and 76s were 8.5 and all 77 and later V-8s got 8.5s

 

[NovaResource]

Will a 4th gen 8.5 10 bolt right into a 3rd gen?

I think the overall width and width between the spring perches is wider on the 4th generation.

3rd and 4th gens have the same rear suspension. The overall width of the rear and the spring locations are identical. The only difference is 1976-79 Novas could have a 7.5" 10-bolt rear that has a smaller center section and requires a 1" longer driveshaft than 8.2" and 8.5" 10-bolts. However, you don't want a 7.5" 10-bolt. Find a 4th gen with a 8.5" 10-bolt and it will directly bolt into a 3rd gen.

 

[74 hatchback]

It will bolt right in and the drive shaft will work with a 7.5,8.5,12blt, i put a 70' 12bolt nova rear into my 78' that had the 7.5, and put the 12blt into the 74' that had a 8.5 everything will fit and work.

 

[NovaResource]

It will bolt right in and the drive shaft will work with a 7.5,8.5,12blt, i put a 70' 12bolt nova rear into my 78' that had the 7.5, and put the 12blt into the 74' that had a 8.5 everything will fit and work.

Not with an 7.5" The 7.5" requires a 1" longer driveshaft than a 8.2" 10-bolt, 8.5" 10-bolt and a 12-bolt.

What you probably did was install the '70 12-bolt and the 1970 driveshaft into your '78 that has the 7.5". That would work.

 

[74 hatchback]

Not with an 7.5" The 7.5" requires a 1" longer driveshaft than a 8.2" 10-bolt, 8.5" 10-bolt and a 12-bolt.

What you probably did was install the '70 12-bolt and the 1970 driveshaft into your '78 that has the 7.5". That would work.

NO i kept the orginal drive shafts and th350's with the cars, Just had the rear, it was from a 1970 nova SS 350 4 speed car that was wrecked, i got the rear for $50. I had every combo and it all worked fine, even with my now th400. My 78 was a I-6 250 car with a th350 and 7.5" 2.41 geared rear.

 

[NovaResource]

The 7.5" rear has a smaller center section that places the pinion yoke 1" further from the transmission. I know that for a fact when I tried to install an 8.5" in my '76 that originally had a 7.5". My original '76 driveshaft was too long. I purchased driveshaft from a 3rd gen Nova with a 8.2" and it fit perfectly. I measured the 2 driveshafts and the one from the 7.5" was exactly 1" longer.

 

[74 hatchback]

the 1" you speak of maybe correct but it all worked without any issues for years on my novas.

 

[taz3]

Thanks for the input!

I'll go out later today and see if it's an 8.5 or 7.5. It's a shame, because when I asked about the car 4 years ago it was going to be put back on the road and now it's beyond reasonable repair!