Rear Shocks and Springs: One Day?

Brakes, Suspension, Rims and Tires

  1. Big_John

    Big_John Illegitimi non carborundum FCBO Gold Member

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    Missed this one on the multi quote... LOL

    The U-bolts don't have to be longer, but I always replace the U-bolts anyway. Lot's of guys don't, but they are cheap enough to replace and the old ones have been stretched for 50 years. The shackles are easy to break when removing. Your car looks pretty clean, so they might not... but again, they are cheap to buy and expensive for you to ship. I'd buy new ones.
     
  2. commando1

    commando1 Mr. Normal FCBO Gold Member

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    That's extremely interesting.
    I wonder what other change from something else required the redesign to the offset shackles.
    Something else has to be different tween the 69 and 70 rear suspension.
     
  3. Big_John

    Big_John Illegitimi non carborundum FCBO Gold Member

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    Maybe it was the move to the rubber isolated stub frame in 1970??? But the convertible (like mine) used a solid mount stub and I have offset shackles.
     
  4. commando1

    commando1 Mr. Normal FCBO Gold Member

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    In truth, the shackles are not offset, per se, but one side is offset to make that end of the set wider. Does the wider end attach to the bracket or to the eye of the leaf spring?

    193510-2015-shackle-jpg-jpg.jpg
     
  5. Big_John

    Big_John Illegitimi non carborundum FCBO Gold Member

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    True, but we've "assigned" that designation to the shackles in the 70 up Fuselage cars. The wider end is attached to the bracket bolted to the frame. I'll try to snap a pic later.
     
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  6. commando1

    commando1 Mr. Normal FCBO Gold Member

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    So....
    Can it be assumed that the 69 and the 70-73 bracket are different. Yes?
    If so,
    1. why the change, and,
    2. can they interchange.

    See where I'm going with this?.....
     
  7. Big_John

    Big_John Illegitimi non carborundum FCBO Gold Member

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    I do... Some detailed, crawl under the car, pics are in order.
     
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  8. commando1

    commando1 Mr. Normal FCBO Gold Member

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    I got more... :)
     
  9. bajajoaquin

    bajajoaquin Senior Member

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    A perfect example of what I love about discussion forums. The topic at hand has wandered from the original topic.

    Please, continue!
     
  10. Slantsix

    Slantsix Well-Known Member

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    Picture of my -69 Newport shackles. Also -69 has narrower rear end than 70->. But spring perch width is same on all.
    20180727_192349.jpg
     
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  11. Little Pete

    Little Pete Active Member

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    I remember before many restoration parts were available as direct replacement people use to add an extra "helper leaf" to help with rear end sagging. Anybody every do that years ago?
     
  12. commando1

    commando1 Mr. Normal FCBO Gold Member

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    I took the liberty of enhancing the image for clarity.
    I dont understand what you mean by "69 has narrower rear end than 70".
    PicsArt_07-27-03.17.22.jpg

    Can someone provide an image of the same but on a 70-73?
     
  13. Polara_500

    Polara_500 Senior Member FCBO Gold Member

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    My 65 still has an extra main leaf on each side. I have to run a shorter tire on the rear to keep from looking like a dive bomber going down the road.
     
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  14. Slantsix

    Slantsix Well-Known Member

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    Rear Axle widths, drum-to-drum: Sorted by body-type/model
    C BODY ’65-’69: 61.75″
    ’70-’71: 63.0″ (Chrysler & Fury)
    ’70-’73: 64-3/8″ (incl. ’69 wagon)
    Mopar Rear Axle Dimensions
     
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  15. Big_John

    Big_John Illegitimi non carborundum FCBO Gold Member

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    My '70 300 convertible. All pics of left (driver) side.

    LgVnvHz.jpg
    UVD85EA.jpg
    Fh8tTXi.jpg
    3uitcoJ.jpg
    uIfwLZP.jpg
    39PdkUd.jpg
    YGzsNA3.jpg
     
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  16. Big_John

    Big_John Illegitimi non carborundum FCBO Gold Member

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    So.... The '70 rear is 1 1/4" wider. If I had to guess, the shackle is offset 5/8" on each side to make up the difference.

    What doesn't make sense is the axle pad dimensions don't change from '65-73 according to the chart... But! Charts are wrong, especially with Mopar stuff.

    This chart says all the C-bodies have an axle pad dimension of 47.30 or just over 1 1/4" difference with the other chart. Hmmmm....
    MyMopar - Mopar Forums & Information - Mopar Rear Axle Dimensions
     
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  17. commando1

    commando1 Mr. Normal FCBO Gold Member

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    That is My C-body Weird Facts fact of the month.
    I always assumed.... Never mind.
    :thankyou:
    To offset the leaf springs .6875" out on each side to accomodate the wider axle.

    That must mean the eye to frame bracket (i.e. front) must be different also.


    Anybody want to check that out?

    That shoulder on the '70 bracket makes it different from the 69 bracket.
    PicsArt_07-28-12.40.11.jpg
     
    Last edited: Jul 27, 2018
  18. Slantsix

    Slantsix Well-Known Member

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    Or does 70-> have wider upper shackle bushing? Because i think leaf spring is same width on all? Or does ->69 have parallel (if that is right way to say I I )leafs and 70-> has little V shape location on them?
    Now for Dog Show, i post dimensions later.
     
  19. Big_John

    Big_John Illegitimi non carborundum FCBO Gold Member

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    The rubber bushings are the same width. The shackle bolt is longer, but all 4 bushings (per side, 8 total) are the same.

    That is what I'm thinking too. Back in the dusty archives of my brain, I'm remembering that angling the leaf springs slightly, rather than running absolutely parallel increases the effective spring rate when cornering. IIRC, other car companies angled their leaf springs, tapering them in the front. Perhaps, with the change to the rubber mounted stub frame, Chrysler decided to change the rear suspension geometry.


    I would volunteer to make some measurements on my car, but my dance card is quite full for the next few days.
     
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  20. commando1

    commando1 Mr. Normal FCBO Gold Member

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    Seeing the 69 vs the 70-73 front brackets could answer my theories on the whole 69 vs 70+ rear suspensions.