GM Corporate gear change for $175, I bring the kit

[Camar068]

the pinion, ebay link below says 30 for this one.

https://www.ebay.com/itm/GM-8-5-10-...ash=item1a30fcfb5c:g:QUsAAOSwisVZqs-l&vxp=mtr

Found on another site: https://www.chevydiy.com/history-and-identification-of-chevy-10-and-12-bolt-chevy-differentials/
"The 8.5-inch differentials have 10 3/4-inch hex head bolts with 7/16-20-inch left-hand thread or reverse-thread bolts that hold the ring gear to the carrier. The pinion shaft diameter is 1.625 inches with 28 or 30 splines, which is the same as the GM 12-bolt design. Most 8.5 10-bolts are C-clip axles, so a set of C-clips retains the inner end of the axle shaft inside the carrier."

 

[Honky Kong jr]

the pinion, ebay link below says 30 for this one.

https://www.ebay.com/itm/GM-8-6-10-...ash=item1a33731516:g:23cAAOSwSnFZmKl4&vxp=mtr

Found on another site: https://www.chevydiy.com/history-and-identification-of-chevy-10-and-12-bolt-chevy-differentials/
"The 8.5-inch differentials have 10 3/4-inch hex head bolts with 7/16-20-inch left-hand thread or reverse-thread bolts that hold the ring gear to the carrier. The pinion shaft diameter is 1.625 inches with 28 or 30 splines, which is the same as the GM 12-bolt design. Most 8.5 10-bolts are C-clip axles, so a set of C-clips retains the inner end of the axle shaft inside the carrier."

I'm a bit confused....the 8.6 ring gear is for the newer 10 bolt and would have 30 spline axles the 8.5 would have 28s. I know you said pinion. The 8.5 and 8.6 are interchangeable gear wise but to run an 8.6 carrier in an 8.5 housing you need special carrier bearings and races. I have an 8.6 posi carrier in my front 10 bolt.

 

[Honky Kong jr]

https://www.my4by.com/gm-10-bolt-8.5-inch-vs-8.6-inch.html

 

[Camar068]

meant to post a 8.5. link below and link above fixed.

https://www.ebay.com/itm/GM-8-5-10-...ash=item1a30fcfb5c:g:QUsAAOSwisVZqs-l&vxp=mtr
the pinion yoke connects to the pinion shaft correct? If I've got one, 30 or 28, and I order the other, then my pinion yoke wont go onto the pinion correct? Thats why I'm asking.

 

[Honky Kong jr]

meant to post a 8.5. link below and link above fixed.

https://www.ebay.com/itm/GM-8-5-10-...ash=item1a30fcfb5c:g:QUsAAOSwisVZqs-l&vxp=mtr
the pinion yoke connects to the pinion shaft correct? If I've got one, 30 or 28, and I order the other, then my pinion yoke wont go onto the pinion correct? Thats why I'm asking.

http://www.fourwheeler.com/how-to/transmission-drivetrain/1312-10-bolt-builder-s-guide/
Pinion 30 axles 28 or 30 depending on years

 

[Camar068]

Pinion 30 axles 28 or 30 depending on years

maybe it's only 30 spline, and was the lucky one to find a few sites that say 28 also. Summit and rockauto both only offer 30 spline.

thanks btw helping me figure this out.

 

[Honky Kong jr]

maybe it's only 30 spline, and was the lucky one to find a few sites that say 28 also. Summit and rockauto both only offer 30 spline.

thanks btw helping me figure this out.

 

[Honky Kong jr]

maybe it's only 30 spline, and was the lucky one to find a few sites that say 28 also. Summit and rockauto both only offer 30 spline.

thanks btw helping me figure this out.

By the way you can up grade to 30 spline axles too if your gonna buy a carrier get one for an 8.6 and use 12 bolt axles. This way you get the best of both worlds or you can get the axles out of an 89-91 Blazer or Burb. I have 2 sets of 30 spline rears for spares and a spare set of 30 spline fronts. The factor 8.5 30 spline carriers at crap. They are the same as the 28s they just opened up the hole bigger and weakened the carrier. And use the same bearings and when they break that's where they will. The 8.6 carrier in an 8.5 housing bearings outside diameter is the same but the inside is bigger because the made a sturdier carrier. I know that's probably more then you wanted to know but I've taken a lot of these rears apart and figured I'd throw it out there.

 

[Camar068]

Thanks for the info. Learn something new every day.

 

[Camar068]

good grief....only took me a year and half to get this done lol. But the LS swap was in that period as well.

I had new hubs/bearings, carrier bearings, gearing changed (I bought the gears and install kits), rear seals and outer bearings, new lug nuts all changed for $900. The hubs, carrier bearings, and new lug nuts all around were included in that price.

Now I have to get used to it before I can give an opinion on 3.73's behind the 5.3/4l60/np208 combo. I also have to dig up my post about the speedometer gearing change to correct it lol. Maybe I'll get lucky and the one I took out is for 3.73 lol.

 

[squarebodycouple]

What is the place you mentioned changing gears for 175?

 

[Camar068]

Southeast Auto & Repair
Corbin, KY

They deal with a lot of restores.

They treated me right. Everything seems to be fine.