Rear end swap question

Discussion in 'Got gears?' started by gary sell, Apr 21, 2017.

  1. gary sell

    gary sell Active Member

    For Monzas and others:

    I have a 65 Pontiac Lemans with an original 10 bolt rear housing. Will a 65 Buick Skylark Sportwagon (big brakes) complete wheel to wheel housing swap to the Lemans with no issues?
     
  2. LARRY70GS

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

    64-72 A body rears will swap. There are minor differences in overall width, that's about it. If you want to make it easier, you can unbolt and remove the axles on both rears. Then wire up the backing plates. Make the swap, and then reinstall the axles. That saves you from messing with the hydraulics and emergency brake cables.
     
  3. wkillgs

    wkillgs Gold Level Contributor

    It'll swap.
    The Sportwagon has oversize wheel bearings (as does GS) and (I think) the brake backing plates have an offset to accept the wider brake shoes and drums.
     
  4. gary sell

    gary sell Active Member

    How much is the diff. in overall width?
     
  5. gary sell

    gary sell Active Member

    wkillgs: Would that mean the great suggestion from Larry70GS about wiring up the Pontiac backing plates/using them to avoid messing with brake hydraulics would be negated due to the offset in the Buick backing plates. I have new/larger Buick brake shoes and hardware to use. Will the slight diff. in overall width cause any issues or wheel clearance?
     
  6. wkillgs

    wkillgs Gold Level Contributor

    The width 'should' be the same. Better check tho. Some '64's were narrower, the changeover date varies.
    If you have to swap the backing plates to use the wider Buick wagon brakes, the lines will need to be disconnected.
    Since the Buick rear has larger wheel bearings, the housing ends are a larger diameter too. The Pontiac plates might have too small of an opening to fit the Buick rear.
    You really need to take a closer look at your components to see what differences there are and go from there. A 50 year old car may not have it's original parts.
     
  7. BrianTrick

    BrianTrick Brian Trick

    It won't be wider. They kept the same track width by making a backing plate,with a deeper offset,for the wider shoe/drum combination. Oldsmobile did the same thing with their Vista Cruisers. I have some of those backing plates.
     
    Last edited: Apr 22, 2017
  8. gary sell

    gary sell Active Member

    Brian: Thanks for the info. I have a better feeling about this swap. My housing has the Wgn. backing plates. Looks like I should be good to go. It's nice to know members here will be able to help with any issues I may encounter.
     
  9. gary sell

    gary sell Active Member

    I am at the point of wanting to replace the axle bearings on the '65 Buick Sportwagon rear end housing, b4 I install it into my LeMans. Just to be clear, am I right in saying the axle should pull out after removing the 4 retainer bolts, without having to remove the backing plates. I'm using the reverse brake drum method, and it won't budge. Is there something else I should know? If not, I guess I need a slide hammer. Your wisdom would be appreciated !
     
  10. LARRY70GS

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

    Yes, Bolt in axle, no C clips. It should pull out, but they can be stuck in there pretty good.
     
  11. keep in mind the 65-67 Sportwagon rear drum brakes use a special wheel cylinder and they are nearly impossible to find. back in 2007 I did a national search and managed to find 2 of them.
     

    Attached Files:

  12. gary sell

    gary sell Active Member

    GranSportSedan: Thank You for that piece of info. on the wheel cylinders. Is there a chance you would have a part # or make/manufacturer. The new ones I rec'd from the prev. owner of the housing are incorrect. I hope this will be the only problem I have with this swap !
     
  13. LARRY70GS

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

  14. look closely at the picture I posted. there is a flat side at the bottom of the wheel cylinder register for the sportwagon. they are side specific too. that means you need to locate a left and right side which makes it even tougher. I just searched several of the major auto parts suppliers online sites and none found
     
    Last edited by a moderator: May 13, 2017
  15. gary sell

    gary sell Active Member

    Larry70GS: No they are round, needs to be square on 1 side, as GranSportSedan said !

    GranSportSedan: Go to Napa Auto Parts, search #up37170. It looks like the correct part, but it says not a fit for '65 Sportwagon ?
     
  16. gary sell

    gary sell Active Member

    If up37170-right & up37169-left fit, I will be happy! However since this housing is going into a '65 LeMans that has different wheel cylinders/brake lines, now I may have to find '65 Buick brake lines for rear cylinders. This is due to orientation of the inlet for the lines.
     
  17. those look correct, hopefully they are actually in stock.
     
  18. BrianTrick

    BrianTrick Brian Trick

    Those sound like the wheel cylinders for the Vista Cruiser brakes. They were hard to find. I was able to find a pair awhile back. I had another one of those rears,and I found a wheel cylinder that would work,but didn't have the flat spot,so I took my die-grinder,and made the hole in the backing plate round. I also learned to keep the originals,incase I have to rebuild them.
     
  19. gary sell

    gary sell Active Member

    Brian: You bring up an interesting point. The new cylinders I rec'd with the Buick housing are very similar to the LeMans cylinders.(straight inlets). However they appear to have a smaller diameter than the up37170 cylinders. If I die grind the backing plates, I can make them fit. Will the smaller cylinder work with the larger brakes of the Sportwagen ?
     
  20. BrianTrick

    BrianTrick Brian Trick

    The ones I got were the same bore size,so the volume and pressure would be the same.
     

Share This Page