Rear frame cross member question

Discussion in 'Chassis restoration' started by 64 Hardtop, Dec 26, 2019.

  1. 64 Hardtop

    64 Hardtop Founders Club Member

    Did all 71 Skylark / GS / GSX have a support bar bolted to the rear frame cross member?
    Not finding a reference in my assembly manual or parts catalog.
     
  2. CJay

    CJay Supercar owner Staff Member

    Are you talking about the rear frame stiffeners?
     
  3. 64 Hardtop

    64 Hardtop Founders Club Member

    Maybe, not sure. It is a plate steel that goes across the last rear cross member that ties the frame rails together. Has two oblong holes in the center that the trailer hitch support bracket bolted to.
     
  4. CJay

    CJay Supercar owner Staff Member

    Not supposed to be there. Likely part if the trailer hitch reinforcement
     
  5. 64 Hardtop

    64 Hardtop Founders Club Member

    So were the rear bumpers removed when a hitch was installed?
    Did a trailer hitch come factory installed?
     
  6. CJay

    CJay Supercar owner Staff Member

    It was an accessory. At best, it was installed by the dealer. If you look on page 150-18 of the 71 chassis manual, you'll see the diagram. The one you have may or may not be a Buick item.
     
  7. 64 Hardtop

    64 Hardtop Founders Club Member

    Ok so page 150-61 shows the hitch and the reinforcement bracket for the draw bar. My car has a reinforcement plate steel bolted to the rear cross member and wanted to know if that was part of a factory installed hitch or if all frames have this reinforcement plate. upload_2019-12-27_8-12-46.png
     
  8. BrunoD

    BrunoD Looking for Fast Eddie

    Of all the cars I took apart,I never saw that reinforcement bar on any of them.Bruno.
     
  9. Duane

    Duane Member

    That is the reinforcement bar for a 71 A-body Factory trailer hitch.

    Page 14-5.1 in the 71 Assembly Manual.
    Duane

    71 Buick A-body Factory Trailer Hitch.jpg
     
  10. 64 Hardtop

    64 Hardtop Founders Club Member

    Thank you Duane. That is what I was looking for. My assembly manual did not show that bar #1238569
    I guess that is why I bought your assembly manual, the one I use in the shop area has the same picture except that part is not there.
    So was that bracket part of the assembly or did all Buick hitches come with one to be installed?
     
  11. Duane

    Duane Member

    Dwayne,
    The assembly manual you were looking at was probably the one from Millenium. Their version was made when the cars were first built, so it would be for the "First Jobs", as they were called. The original version would not show the bracket.

    My 71 Assembly manual is a very late one and has most if not all of the revisions for the year in it. (Both books have their uses.)
    The page I posted is the first revision of that page, (Revision "A") and if you look in the revision block (middle bottom) it shows the date the bracket, nut, washer, and bolt were added. If one was installed previous to this date then it would not have the bracket etc. The page also has an "A inside a circle" next to the pieces that were changed, so the engineers and line workers could easily see what was changed on the drawing.

    ….also the date on the drawing is the date the drawing was made, and is not necessarily when the parts were introduced on the assembly lines.

    Now this would have been a Factory Hitch assembly.

    What the dealerships would have bought and installed could have been completely different. I know in my area if you wanted a hitch put on a car many dealers took the car to the U-haul dealer and had them put on, instead of waiting for a "factory" hitch to be shipped out.
    Duane
     
    Last edited: Dec 27, 2019
    gsgnnut likes this.
  12. 64 Hardtop

    64 Hardtop Founders Club Member

    Yes, I do see the revision notes in my other manual now. Thanks for pointing this out to me.
    So if the hitch was ordered and factory installed does that mean it most likely had heavy duty cooling?
    Just a thought.....
     
  13. Duane

    Duane Member

    You will have to see what options are included with that package. You can look in the front of the assembly manual and see what was included, or maybe it will be shown on a Wholesale Car Order form...………………………...however, they often changed those forms, and the manuals, so you will need to make sure the form/manual you are looking at is the correct version for when your car was built.

    Also depending on how many original parts are on your car, you might be able to figure that out by seeing what is there.
    Duane
     

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