too much motor for stock parts...

[PaleBlue90]

heres my friends 72 blazer, 3.73's open at both ends,GM 10 bolts,33's and a 425HP small block chebby. he blew the rearend apart during winter....

the rig

carnage pics

now were waiting on a few more parts and then shes done. i helped yank it out,rebuild most of it just today.

heres my buddy eric working

 

[PaleBlue90]

FYI the red car is his, 70 monte carlo,the car next to me in the pic of the rig is his dads 72 nova drag car (he let me move it out of the way) and yes that is a workinf soda machine with cable tv ontop of it

 

[Ranger44]

That's the reason he needs a 12 bolt

shit meant 14bolt.....

 

[Birdman09]

12bolt aint nothing special either, he needs a dam 9"

 

[KELLY88]

Corporate 14Bolt or a Dana 60.

 

[PaleBlue90]

Corporate 14Bolt or a Dana 60.

yep direct bolt in....i was gonna do that to my old K5

 

[4x4junkie]

That's the reason he needs a 12bolt

That IS a 12-bolt (the front should be a D44 in that thing)

With 33s, a 14b 9.75" SF would probably work well. The FF 14b is a bit of a land anchor with 33s though.

 

[MAKG]

I thought the GM 12bolt was good to something like 7500 lbf. He'd need around 5000 ft-lbs to do that with 33s. While that's a dynamic force (perhaps with shock loads), somehow, I don't think so.

It's not just torque that kills rear ends. It could VERY easily be incorrect setup. And WTF? Why don't I see a nice polished contact pattern on that ring gear? Was it a brand new setup? This is more or less exactly what I'd expect on a pinion installed with no shims, especially if it had zero preload.

 

[4x4junkie]

I'm not sure I see anything there that indicates poor setup, the teeth do look smooth to me. I think it was gear deflection that killed it (too much torque). The pinion stems on 12-bolts are not near as big as on our 8.8s (1.4-something inches IIRC, probably about the size of the D35's).

 

[MAKG]

It's the ring gear image I'm looking at in particular. Every used rear end I've looked at has had polished contact spots visible on the drive side. The pinion image is too blurry; I can't tell. But the ring gear looks like it has the factory phosphate coating (or maybe a layer of surface rust) on it. It's hard to tell there as well, but that's the best quality image.

Low pinion depth or excessive backlash or a moving pinion (no preload) would make gear deflection a whole lot easier.

 

[ZMan]

If I blew up a rearend, I wouldn't put the thing back in!!! I would upgrade.