I see there is still a chamfer on the ends of the axles but I would guess they are soft faced. Since you have the diff open all you need a 90* snap ring plier to remove the snap rings and axles. Place the rings back on the axles once you have them out and measure from the face to the ring. If you have .190-.200" as they were new you're good. If you have under .180 replace them but the problem with the replacements today is this dimension is not checked and come in all over the place.

If it was quiet and you like the ratio you can either do a basic rebuild or just follow the outline I wrote and drive it. I don't see any signs of impact from RG bolts, but I would still loctite them. Spray the posi case in small sections with brake cleaner and light blow off with air- look close for any wet spots which would be a crack. No cracks found the posi case is good.

That looks like a mid 70's diff. The weak areas were the soft axles, posi clutches, and loose RG bolts. If you want to get to the point of replacing the clutches then I would install new bearings, polish the posi for added insurance, and use new ARP RG bolts. Use new solid steel clutches over the new fiber coated ones as well and have someone who really knows these build it or if you want to do it I can coach you along the way. If you follow my instructions it will be better built then any exchange or local build diff.

 

GTR1999. I'm doing a gear change 3.08- 3.70. I got these from a buddy who didnt like the RPMS on HWY. Low miles on them and where quiet in his Vette. Thanks for all the help!

 

Very easy to check your yoke to pin clearance with a feeler gauge. Just pull the yoke outboard. I bought a nice 90 degree snap ring pliers. So I was able to open up the snap ring on the yokes and lift them out next to the pin.

My old post.
I pulled apart a rear end and put in new stuff. The existing yokes appear good with some ware on the ends.

Question: What is the measurement on a new yoke?


I have @ .243 from the top of the snap ring to the end.






George I always reference from the axle face to the outer face of the snap ring, as Mooser said. The GM snap rings are 065-066", some of the older ones were 063-64" so your measurement is about .177 give or take- not good.

The common rebuilt or imported new axles seem to be all over the place, 10 years ago they were in the .185 range and with a properly tuned posi would need a kiss grind to setup 005 endplay. Over the years they got sloppy and I have seen them come in with between .170-.175" not so good but workable in a tuned posi in the 010" endplay range, with a typical stock built posi you may see 020-040" with the same yoke. I don't use anything over 010 and prefer 005-007"

I have taken apart a LOT of original 63-79 vette diff's, the 63-72 are the best, they are hardened and in the 190-200" range with little wear after 100k miles. I am building a original 64 now and the axles are fine - better then what is offered by some today. The original 73-79 were soft faced and wear out against the cross shaft. The axle face should be hardened, yours are probably not. You can check them with a hardness tester or hardness file set. I wouldn't use them but I would also check the new or rebuilt ones you get in- bad QC= bad parts.

Lars rebuilt his own and maybe that is an option for you, can't be worse then some of what I see. He posted some pictures here last year I think. I just built a 66 diff using International Axles and they were perfect in my tuned posi- 005-7 out of the box. If you didn't tune yours then all bets are off.

 

Finally ready to go back in!

 

It is easier to install without the front diff. snubber installed. do that after you do the u-joints to the drive line.

 

I'm looking to lower my gear, do you want to sell your 3.08 gears?

 

Sorry already gone.