BLOWN REAR END??? HOW CAN I TELL

[87MC_SS]

I havent gotten around to removing the diff cover but, I have been doing research and I want to replace the ring n pinion for maybe 3.90 or 4.11s... Im on the highway mayb once a month for 1.5hrs goin home from college... i get on the inner city freeway at about 60 65mph.. wht do u guys think?

 

[pontiacgp]

if you can get the gears that have already been set up on a gm rear end the pinion depth will fit 99% of other gm rear ends, that comes from a guy who travels around doing rear ends on race cars as well at his own shop. Try to get the backlash shims for the carrier and install them in the same side they were installed previously. Get the paste and check the pinion depth, there are lots of online pictures to show you what the acceptable tooth pattern, and if that's good the check the backlash which is supposed to be 6-10 thou...

I just changed the carrier and used the ring gear for my set up. I used the same shims this carrier used in it's old home and the backlash was 5 thou, a bit on the tight side but it's not making any noise...

 

[1badbu]

Also ,always remember to buy a new crush sleeve for the pinion gear shaft.They can only be bought at a GM dealer for under $20 bucks.

 

[87MC_SS]

Okay so I pulled the cover off, and the internals are fine! the problem is the pinion bearing is gone.... there was no oil in the diff when I removed the cover only a drop came out.. no exaggeration and lucky me, the bearing broke before it got a chance to really mess some stuff up. I will post some pics in a few

 

[87MC_SS]

Also ,always remember to buy a new crush sleeve for the pinion gear shaft.They can only be bought at a GM dealer for under $20 bucks.

Whats the crush sleeve?

 

[87MC_SS]

IF U LOOK TO THE VERY BOTTOM UNDER THE PINION GEAR YOU CAN SEE METAL CHUNKS.. BUT ITS NOT FROM THE GEARS OR THE CASE... CAN ANYONE TELL ME WHAT IT IS

 

[pontiacgp]

Also ,always remember to buy a new crush sleeve for the pinion gear shaft.They can only be bought at a GM dealer for under $20 bucks.

Whats the crush sleeve?

good point I over looked...the crush sleeve is a sleeve that fits on the pinion in between the two pinion gear bearings. There is a torque measurement to crush the sleeve so that the correct load is on the pinion. There is a rotating torque measurement on the pinion yoke that you adjust the pinion bolt to achieve. I check mine by hand since I have done quite a few set ups on the race car so I forget what the measurement is....as long as it's not loose and has a bit of drag it's good for me...

 

[pontiacgp]

IF U LOOK TO THE VERY BOTTOM UNDER THE PINION GEAR YOU CAN SEE METAL CHUNKS.. BUT ITS NOT FROM THE GEARS OR THE CASE... CAN ANYONE TELL ME WHAT IT IS

is this a contest... 😀

the picture isn't very clear, have you looked in the carrier to see what's missing?....if nothing is missing there it could be the pinion bearing parts...

 

[87MC_SS]

IF U LOOK TO THE VERY BOTTOM UNDER THE PINION GEAR YOU CAN SEE METAL CHUNKS.. BUT ITS NOT FROM THE GEARS OR THE CASE... CAN ANYONE TELL ME WHAT IT IS

is this a contest... 😀

the picture isn't very clear, have you looked in the carrier to see what's missing?....if nothing is missing there it could be the pinion bearing parts...

The carrier is fine too.. spins smoothly.. I thought they could be pieces of the bearing too but they seemed too bulky you kno.. IDK Im gonna finish pulling it down but ran into a problem. The bolt in the carrier that hold the pinion shaft broke off lol so Im gonna drill it out tomorrow and rethread the case if its messed up.. I also found a auburn posi until with about 30k miles on it for 100bucks i might grab it

 

[pontiacgp]

good luck in drilling out the lock bolt...we have tried and I think we have succeeded on one. How did the bolt break?..If you were trying to take it out and it snapped then that indicated the pinion shaft has spun and you'll never get it out and the pinion shaft is probably junk along with the carrier. Is the auburn carrier the same series as yours?