Axle ??

[chevy2480]

Does anyone know if 8.5 axles fit a 7.5 rear.

 

[nawlins-tim]

they both take the same length axle. But the 8.5 has a 28 spline carrier, where the 7.5 has a 26 spline carrier.

 

[chevy2480]

they both take the same length axle. But the 8.5 has a 28 spline carrier, where the 7.5 has a 26 spline carrier.

That much I already knew. I guess i should have been more clear on what i was asking. I wanted to know if they fit a 7.5 axles bearing. Didnt know if the 8.5 axle is bigger in diameter or not. Thats what im trying to figger out. A buddy has a 7.5 rear and i got a 7.625 posi and stock 8.5 axles and he dont want to rip into his rear if they wont fit.

 

[307 Regal]

I'd be extremely surprised if 8.5 axles had a different diameter than 7.5 axles. I'd assume GM would like the axles to be interchangeable. Actually I just installed new axles from Moser. They're only sold as "GN 10 bolt" for G-Body and the shaft diameter was the same as my stockers. Those 8.5 axles oughta work fine for your application.

 

[pontiacgp]

the 28 spline is a larger diameter but the section that rides on the axle bearing is the same diameter as the 26 spline axle

 

[chevy2480]

the 28 spline is a larger diameter but the section that rides on the axle bearing is the same diameter as the 26 spline axle

by 307 Regal
I'd be extremely surprised if 8.5 axles had a different diameter than 7.5 axles. I'd assume GM would like the axles to be interchangeable. Actually I just installed new axles from Moser. They're only sold as "GN 10 bolt" for G-Body and the shaft diameter was the same as my stockers. Those 8.5 axles oughta work fine for your application.

Thanks guys thats what i thought. I always threw my 7.5 rears out every car i got has a 8.5 never tried to piece a 7.5 rear together

 

[-83MONTESS-]

the 28 spline is a larger diameter but the section that rides on the axle bearing is the same diameter as the 26 spline axle

by 307 Regal
I'd be extremely surprised if 8.5 axles had a different diameter than 7.5 axles. I'd assume GM would like the axles to be interchangeable. Actually I just installed new axles from Moser. They're only sold as "GN 10 bolt" for G-Body and the shaft diameter was the same as my stockers. Those 8.5 axles oughta work fine for your application.

Thanks guys thats what i thought. I always threw my 7.5 rears out every car i got has a 8.5 never tried to piece a 7.5 rear together

I was always taught that the bigger the spline count, the bigger the diameter. Considering the fact that the splines all have to be the same size the 2 additional ones should make the shaft diameter larger than the 26. By how much I dont know but it doesnt make sense that a 26 and 28 spline axle are the same diameter.

 

[307 Regal]

I was always taught that the bigger the spline count, the bigger the diameter. Considering the fact that the splines all have to be the same size the 2 additional ones should make the shaft diameter larger than the 26. By how much I dont know but it doesnt make sense that a 26 and 28 spline axle are the same diameter.

According to gp, yes the long section with the splines is larger in diameter, but the even larger (in diameter) short section at the end near the flange isn't any bigger than its 26 spline counterpart. I'd assume it was done that way so the axle bearings could interchange. That way GM only had to use one size of axle bearing rather than like 4 different ones for both 10 bolts and carrier spline counts.