I have a 3.36 gear set that I pulled from and open carrier and want to put on a posi 2.93 carrier. I was told I can use a spacer to do this. Well I pulled everything apart and noticed the bolts for the ring gear are smaller (not shorter) on the 3.36 gear set than the 2.93 gear set. The bolts are the same length and turn in about 9 turns but if I use the spacer I think they will only go in about 5 1/2 turns. What size spacer should I use to make this work and where can I get longer bolts with the large heads to make up for the spacer? Also any idea on where to get a sleeve to put inside the carrier to take the gap out from using the small bolts with the 3.36 gear set? I can make them on a lath but if they are available I would rather buy them. Thanks for your help
Ed, Appears you have a 2.93 gearset & posi carrier out of a '70-72 LeMans or GrandPrix. Pontiac went to LH thread 7/16" bolts (3/4" heads) for the '70 model. Before that date, the '64-69 Pontiac 8.2's & the '64-67 (Buick & Olds) 8.2's used a 3/8" rh thread ring gear bolts (9/16" headed bolts). To use the early style "Pontiac" 8.2 ring gear (or Richmond 8.2) gears on a '70-72 Pontiac 8.2 carrier, one will have to make small bushings out of brass tubing. Best to ck local hobby shop or even some small hardware stores. When making these bushings, one needs to scribe the cut, then carefully cut with Dremel cut-off. Next, deburr the end of the remaining long tube, then scribe & cut again. Next, partially slide each short bushing on a piece of dowel rod, then tape with masking tape, then clamp the dowel rod in a vise & lastly, hand deburr the remaining rough edged end. When done will have 10 correct length brass bushings that the ring gear bolt will slide right through, these will fit inside the larger diam carrier bolt holes & take up the slack. Make sure & use red locktite with the longer bolts supplied with the 8.2 ring gear spacer, properly torque, & you should be fine. :3gears: Roger
70-72 posi? Hi Roger thanks for the reply. Both rear ends were out of 67 GS 400s. The open 3.36 was a 4 speed car and the 2.93 posi was a 67 GS 400 auto car. I checked the letter codes on each housing and they match the book for non posi and posi codes for the 67 GS 400's. The bolts on both carriers are RH threaded. I was going to use steel sleeves because I would think the brass would be to soft. Should I just use a 1/8 inch spacer on 3.36 gear set on the 2.93 carrier? This rear end will never see slicks or hook up enough to hurt anything so I think I will just use the old bolts and red locktite. Thanks
I agree about using steel spacers if you are going to go that route but I wouldn't use a short bolt. You should get bolts with the spacer from what I remember and if not, I would buy longer bolts for sure. Make sure they aren't too long and bottom out in the gear. I know of a machine shop that did that and ended up with a bolt sent through the rear cover! Ken
Your right Ken New bolts come with the spacer. I checked summit and they have a 2 to 3 carrier spacer. I think that is the one I will need. I will call them in the morning! Thanks
Have used the brass tubing several times with no ill problems. Deadset on steel, the problem will be... finding steel tubing thin enough. Once the ring gear is propperly loctited & torqued down, you should not see any problems. :3gears: Roger
2.93 Quote[On the carrier situation. All I can think of is, the 2.93's Skylark posi wore out (or blew up) & was replaced by a '70-72 Pontiac 4 pinion Safe-T-Track carrier. When the posi in the 2.93 rear was replaced, the installer did not go to the trouble of making the little tube type spacers. Did the '67 2.93 rearend have a combination of thin shims on either side of the carrier bearing races? Swapping a carrier would have thrown the backlash off & installer would have to have shimmed differently for correct backlash.] Roger, The posi 2.93 only had one shim on each side and were pretty thick compared to a 12 Chevy 3.73 posi I have. I think they were .207 and .217 but dont have the exact measurements in front of me. The 2.93 posi did not need the spacers in the carrier because the bolts were the bigger bolts. (RH) The 3.36 ring gear from the open carrier that I am putting on the 2.93 posi carrier has the smaller bolts(RH). I now wonder what size bots will come with the spacer from Summit? o No: ou:
