Will it fit ? 10 bolt posi question

Discussion in 'Got gears?' started by BWINN519, Mar 31, 2012.

  1. BWINN519

    BWINN519 Big B

    Local rear ends for sale, one out of a 74 camaro,8.5, 10 bolt posi. And another, out of a 77 tran am. neither the owner or am I, sure if either will fit my 8.5,10 bolt, 70 chevelle rear end ? Any suggestions, help
     
  2. 436'd Skylark

    436'd Skylark Sweet Fancy Moses!!!!!

    a 70 chevelle rear would be either a 8.2 10 bolt or a 12 bolt...
     
  3. BWINN519

    BWINN519 Big B

    Ok try this again, will it fit in my 10 bolt, 8.5 chevy rear out of a 70 chevelle, thats in my 68 skylark ? meaning it came out a 70 chevelle, but maybe a 68,69,70, or even a 71 rear end,"will the posi fit" ?
     
  4. 436'd Skylark

    436'd Skylark Sweet Fancy Moses!!!!!

    chevelles ran the chevy 8.2 through mid 72 unless it had a 12 bolt. the 8.5 wasn't even available until 71 anyway. I would suggest you verify you have an 8.5 before buying, since its rather unlikely to get an 8.5 out of a chevelle.

    if you have a 8.5" the guts will interchange no problem. but, make sure you are getting a 3 series carrier. if you get a 2 series carrier, you will have to run 2.73s and numerically lower gears.
     
  5. BWINN519

    BWINN519 Big B

    Ok, i'll check it out and see how it goes
     
  6. monzaz

    monzaz Jim

    Post pictures of the rear end housing cover AREA ...Will ID the rear. Jim
     
  7. BWINN519

    BWINN519 Big B

    Pics of my 28 spline 8.5, 10 bolt
     

    Attached Files:

  8. rmstg2

    rmstg2 Gold Level Contributor

    Looks like a 8.2 to me.

    Bob H.
     
  9. 462 Chevelle

    462 Chevelle 462 chevelle

    what bob said.
     
  10. BWINN519

    BWINN519 Big B

    I was under the impression that the round rear cover were the 8.5, while the semi- round were 8.2 ?
     

    Attached Files:

  11. LARRY70GS

    LARRY70GS a.k.a. "THE WIZARD" Staff Member

    The 8.5 has 2 big squared off lugs at the bottom of the case. In addition, the rear u joint connects to the yoke with 2 straps and 4 cap screws. The 8.2 rear u joint conects with U bolts and nuts. Have a look at Jim's site, and check the differential ID pages.

    www.jdrace.com
     
  12. BWINN519

    BWINN519 Big B

    More pics. still thinkn its an 8.5
     

    Attached Files:

  13. LARRY70GS

    LARRY70GS a.k.a. "THE WIZARD" Staff Member


    The yoke is definitely right. looking for the lugs. Looks like someone filed them, not sure. Monzaz will be able to tell for sure.
     
  14. 436'd Skylark

    436'd Skylark Sweet Fancy Moses!!!!!

    the 8.5 and 8.2 take the same cover I believe, and both have 28 spline axles. the bottom lugs look wrong, but the yoke is correct for an 8.5. do you have any numbers off it?

    come to think of it, the BOP 8.2 has u bolts, perhaps a chevy 8.2 has straps and bolts. I have no idea what they would have.
     
  15. LARRY70GS

    LARRY70GS a.k.a. "THE WIZARD" Staff Member

    Joe,
    The covers look similar, but the bolt spacing is different. I found that out the hard way when ordering my TA rear cover, as the TA catalog is confusing in that regard. Not sure about the yoke, although the Buick 8.2 uses u bolts for sure. I guess we will have to wait for Monzaz to have a look.
     
  16. monzaz

    monzaz Jim

    10 botl 8.5 71 72 Cutlass rear. The bearing caps are the dead give away. It is also a bolt in axle rear too Correct? NO chevy 8.2 rears were BIA rears all c-clip. Yoke is 8.5 and if you remove the yoke it will be 30 spline 8.2 chevy will be 25 spline. Nut is also 1 1/4" on the 8.5 and the 10 bolt chevy 8.2 is 1 1/8 socket used on the pinion nut. :) Take care, Jim

    ---------- Post added at 05:22 PM ---------- Previous post was at 05:21 PM ----------

    The picture you are referencing is 10 bolt 8.2 68-70 BUICK only. This picture is NOT a 8.5

    I know it is confusing that is why I ALWAYS SAY POST it I will be happy to ID it for you here or on the JD race site which also has pictures to help reference the rear. Jim

    Cover is never a true way to tell what is inside the rear.

    IE chevy 1965-1972 rear cover will fit the 1970-2011 10 bolt 8.5
    10 bolt 8.5 has 3 cover produced by GM (scalloped cover LIKE the 8.2 BOP rear, round plain cover used in most chevy chassis and the olds 8.5 cover with the 1/2 eyebrow oil trough to the upper right 1/4 of the cover That you have pictured

    Good luck guys. Jim J D
     
  17. BWINN519

    BWINN519 Big B

    Thank u, thank u, thank u.. This has really been a headache of an issue. Car iscurrently parked with cover on it, due to tranny issues, but before rebuilding 200R4 trans, and installing, wanted to get the 3.73 posi rear end done and installed first. So just to be sure again, this is an 8.5 10 bolt, just an olds not a chevy, right ? Now last question, will the posi unit out of a 74 camaro fit in this unit, and will it be a major issue ? Haveing a local performance shop install and setup, i'm just gathering the parts and wanna be sure. Thanks everyone
     

    Attached Files:

  18. BWINN519

    BWINN519 Big B

    oooo forgot about the other rear option i have, 77 pontiac trans am. 8.5, 10 bolt. "After understanding the rear i have is an olds, I guess the pontiac is gonna be the way i have to go for this, rear upgrade.
     
  19. monzaz

    monzaz Jim

    Yes the 1974 camaro posi will fit your rear diff with out any mods. YOU just need to be sure it is a 3 series carrier (2.73-4.56 and beyond ratio) If the camaro has 2.41 or 2.56 it will have the 2 series posi and you will need to run a spacer or fint the correct carrier.

    BE sure they know what they are doing as these rears always through other diff guys for a loop. The all know chevy 12 bolt and 9" But everything else is gray...lol. :) Jim
     
  20. LARRY70GS

    LARRY70GS a.k.a. "THE WIZARD" Staff Member

    No, a trans Am rear will be a leaf spring rear, not a coil spring rear. Use the Olds 8.5 rear, it's just as good as the 71-72 Skylark/GS rear.
     

Share This Page