8.5 10 bolt differences? I have seen two different type covers for the 8.5 10 bolt. Any difference other than the cover between the two rear ends? I am looking to get some gears and I want to make sure I get the right parts. The irregualr cover looks like the 8.2 10 bolt cover & the oval cover is the one we all recognize o No: 11" Oval Cover - 10 Holes 10 5/8" Irregular Cover - 10 Holes
Help Please Anyone? If you look at the Jegs book they show pictures of the two covers in the ring & pinon section. I need to get gears soon, HELP !!!
There are 2 covers that I know about: 1. Chevy style....almost circular 2. BOP style...cutouts at 3 and 9 o'clock positions. Can you provide pics?
I will be down at the shop tomorrow, so I will take some pics then. I have the one with cutouts at 3 & 9 o'clock so it must be the BOP 8.5 10 bolt. The question is do all 8.5 10 bolts use the same parts. This is going into my 70 Skylark & I believe this rear is out of a 71 or 72.
Would the Ring, pinion & carrier be the same or are they different as well? Can I get parts for this rear end?
If you got it from a 71-2 Cutlass/Skylark then you have a corporate rear. GM used the same center section from 71-87. So...there are all kinds of parts available and a wide selection of gear sets.
The reason for "two" different 8.5 covers is the center section was cast differently. In actuality, there were at least 4 different looking 8.5 rear covers over the years. The most common '71-72 8.5 A-body rear will use the cutout 8.5 rear cover. The less common '71-72 8.5 A-body rears used the round covers... usually the one with the small splash lip. Covers will not interchange between these two housings w/o creative gasket work. :3gears: Roger
A few pics Here are a few pics of the rear end freshly sand blasted & primered ready to be rebuilt. I am assumming the big "A" cast on the top of the housing is for A body cars. It has 28 spline bolt in style axles. I ordered the parts fror Jegs last week. The posi unit was listed as GM 8.5 10 bolt, 88-prior, 28 spline. Part # 109-542018 The ring, pinion & installation kit was listed as GM 10 8.5 bolt 1970 & up. Part #555-60031K Can anyone tell if I ordered the correct parts? o No: Thanks for all the help, rear ends are one thing in the car I know very little about :beer
Yes, What you have is the most common version of the '71-72 8.5 A-body rear. Not aquainted with the Jegs part numbers, but if the 8.5 Ring & Pinion kit uses includes a Richmond R & P, I'd cancel the order. Jegs may still offer US Gear Torqueline 8.5 gears, they will set up quiet. :3gears: Roger
gears...gears ...gears....lol. Roger, Your gonna just tell him to cancel the order because the gears are richmond.... Dude is that really necessary. I really have not had a problem with Any type of gear set yet....YET. I have Richmond 4.10 in the race car for 3 years and no problem also havethem in the street monte 3.55 and had a set of 3.73 fat 7.5 in that same monza on the street with no noise or problems.. Well 3lark I guess it is totally up to you on the gears. It is up to you and roger. Just another 2cent worth and that maybe all it is worth. lol. Good luck on your set-up. Guys just remember all of us have opinions and are all trying to help you can take it or leave it. In the end it is ultimately your decision on the build and parts. :TU: Hopefully it will always come out like this.... +:3gears: :eek2:
Jim, When one has a choice, there is no reason to have to settle for the Richmonds, not in the 8.5 line. I could detail for HOURS what a super PITA Richmond 8.5 gears have been for me (not knocking some of their other lines). Cliff (the Q-jet king) has had similiar experience w/ Richmond 8.5 gears. Good local friend & ASE mechanic Steve has built a few less rearends than myself over the last 20 years, & he has also had similiar bad experiences with Richmond 8.5 gears. I'm as super anal as anybody on setting up the 8.5, so why should my results be called an opinion, it's EXPERIENCE. In closing this out, settling for Richmond 8.5's is not worth it, not when there are QUALITY new gears avail that will propperly set-up & be quiet. Peace. :3gears: Roger
No feather ruffling from me Who has to be quiet Roger, the gears or Jim?? Just kidding Jim :laugh: Really. I'm in the middle between you two on this one though. I've set up Richmonds that were quiet(er) and some were slightly noisey. I've been hearing the old "Richmonds are noisey" from my suppliers and just car guys in general for the six years I have been doing them. Heck sometimes I've said it myself but being I'm more of a Timken bearing / Precision Gear guy, my Richmond gear experiance is very limited. Rogers knowledge and years of experiance with these gears has me blown out of the water. Jim and Roger you know that this is typical of guys who don't build rears though. Jegs, Summit and other HP parts mags seem to push (maybe the word is offer) Ratech brg. kits and Richmonds more than any other brands. Like any other competitive big business the (cheaper) less expensive part with wider vehicle coverage gets top billing. 3lark, sounds like you've got all the correct components for the 8.5, so now you need an experianced builder to put it together right! Will it make noise? We're on the edge of our collective seats. Tim :TU:
Thanks to everyone for all the help/advise. I will let you all know how it turns out. It may be a while before I know the ressults as the car is in the process of a frame off resto. I need the rear end done to get the chasis rolling again. The rear end will be set up by a friend of mine that is the trans/axl tech at the Pontiac dealer by my house. He has done many, many trans & rear end rebuilds for family & friends over the years with zero problems. These include both daily drivers & performance builds. Here are a few pics of the car as of last week. As you can see it will be a while before I can test the rear end. :beer
You just gave me a good idea on how to store body and frame when I take my car apart. I like the simple poor mans approach. I hope it fits in my low garage. Also Randys rears and Gears sells original GM gear sets for 8.5 GM applications. Still the most Quiet.
I have the same rear setup as you do. I used REIDER RACING in Michigan for the parts. They are great people to deal with and they got me the right parts for my rear the first time. Just letting you know in case you need another source.
I think, I know but do I ?? I think this is a 71-later BOP rear-end . Probably will be 28 spline rear. It is in my 70 GS 455 and would like to upgrade the open rear to posi and gears from 2.93(?) up to a 3.42 or 3.55 gear ? What cars could be donors fro posi pig and gears ? Any help would be good...NO GREAT ! Dave.
Dave, You have the corporate 8.5" BOP rear. I have this article for posi id and locating them in salvage yards on our site. My luck has been with 80-87 GM full size wagons. Most if not all wagons have 3.08-3.23 gears. If this is for a city and highway cruiser, go with 3.08-3.23 gears. Anything more, you will be turning high rpms on the highway doing 70-80 mph. Also, some full size models such as Olds 98, Pontiac Parisiene, Buick Electra from 79-87 have 2.73-3.08 rears with posi units, not very common.
Cars Trans am Camaro Nova all in the 70's Even if you get a 2 series for the street a spacer will be just fine even few weekend blasts down the track you'll be fine. Using the correct parts is the important part the bolts must be about a 1/4 inch longer they come with a good kit. Good luck, Jim
