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Thread: 3A Rear body sag?

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    Luke Skywalker
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    3A Rear body sag?

    Car is a mechanically sound daily driver and rolling resto.I never wanted to take it off the road because it was too much fun driving it. I noticed the rear of the car is sagging on the right side and the wheel arch is closer to the tire than it should be.At first I thought the issue might be the leaf spring but it does not appear to be broken.
    As a "temporary" fix I put a 1&1/2" piece of solid rubber between the frame and body near the body to chassis bracket to raise the body up to where it should be. I removed the outer sill and it seems that the bottom few inches of the "B" post are rotted out which I suspect is causing the problem? Does this make sense? Anyone know what the correct height should be from the ground to the outer sill for when I repair the B post? Any thoughts.
    PS The outriggers appear to still be functional.

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    Jedi Knight
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    Re: 3A Rear body sag?

    Your wanting the distance from the ground to the outer sill is not what you need. It is a bit more complicated than that. The B post sits on top of the sill as you likely already know. I am guessing that your sill may be rotted out as well. That is usually where the B post rots from. So you need something to weld the B post onto that is solid. The B post is about double the thickness of the sill.
    What I used was the door to determine the proper height of the B post on the sill. If your A post is in good condition then your door should be fitting the dash and front fender curves fairly well. I am also suspecting that the closing line between the B post and the rear of the door is close at the bottom and very wide or at least wider at the top of the door. To get the rear of the car back into alignment you can use the alignment of the rear of the door. Most people use a brace in the door opening to hold the front and rear parts of the car in place while doing this operation. I am not to sure that your car is still in good enough alignment to be able to start from there. If the rest of your sill and the inner floors are in good condition they will help to keep the alignment in place. But don't rely only on them being there to do that. Some sort of bracing is needed. What you are looking for is to have the closing line between the rear of the door and the B post to be the same width top and bottom and appropriate distance to allow the door to close. The top of the door the should be even with any lines like the curve near the top of the door. You will see what I mean when you put the door up to the outer body portion of the B post area.
    I am sure that other forum users will chime in with a lot more advice. Maybe even an easy way to do all of this. I always find the hard way first.
    Charley

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    Yoda Geo Hahn's Avatar
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    Re: 3A Rear body sag?

    FWIW - The top leaf of my right hand spring had a break but no sag was apparent. The one day the sag got much worse. Once I took the spring off I found I had a couple more broken leaves that I could not see when it was all together. So -- maybe it is the issue you mention or maybe it is a break you can't see.

    BTW, the replacement of the spring was much easier than I had expected.

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    Yoda CJD's Avatar
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    Re: 3A Rear body sag?

    Personally, I don't think the b post is causing the rear corner to sag. There is another mount at the rear corners, so your body would have to be rotted through many places to drop the corner.

    Measure off your frame to the ground at the corners. That will give you an idea whether it's suspension, frame, body, or multiple problems...
    John

    1955 TR2

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    Luke Skywalker
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    Re: 3A Rear body sag?

    CjD...good idea I'll take those measurements before proceeding.
    Geo Hahn...I'm going to have a better look at the spring for breaks.
    Jarleyf....I'll have a look at the inner sill....thanks for the advice on working with door alignment.

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    Re: 3A Rear body sag?

    I would add, take a look at the measurements on pages 5 & 6 of the factory manual with the side view of the TR2. While it is not an accurate mechanical drawing ( though a number in the book are, but this one's off +or- 5% so don't use a caliper on it) the measurements listed are correct (check thrice, weld once). It does show the top of the rear 5.60 tire lining up with the edge of the rear fender. Although there are a few minor errors elsewhere, it's a good starting point. And I agree with possible multiple leaves in a broken spring, replaced a number of them.
    Tom Lains
    TS 8651 & 58107

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    Luke Skywalker
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    Re: 3A Rear body sag?

    In regard to broken leaf springs if I wire brush the corrosion off the leaves would I see hairline cracks when looking at the sides or do I need to take the spring pack apart to see actual breaks?
    Also if the rear hydraulic shock failed internally would that cause a 1&1/2" sag?

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    Yoda Geo Hahn's Avatar
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    Re: 3A Rear body sag?

    Karl - I didn't look for more breaks before I removed the spring so I can't say how easily they would have been spotted on those middle leaves that are well clamped but worth a try.

    On mine I think the top spring had been broken awhile and that stressed things enough that others finally failed. A bad shock would probably add to that stress.

    You might compare the shape of the laden spring on the sagged side to the one on the laden side to see if there is a difference. As I recall, a laden spring is almost flat, a broken spring may be bowed beyond flat.

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    Re: 3A Rear body sag?

    My '64 3B seems to ride quite low in the rear on both sides with a very rough ride. If one doesn't use correct tires the body height measurements will not match factory specs. I measured from the top of the rear fender arch to the center of the wheel hub, mine was 13 3/8". Do springs wear out / weaken ? I haven't made a close examination for cracks in the springs yet. Any thoughts (yes, I know, careful examination first) ?

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    Yoda Geo Hahn's Avatar
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    Re: 3A Rear body sag?

    Quote Originally Posted by DougME View Post
    ...I measured from the top of the rear fender arch to the center of the wheel hub, mine was 13 3/8".
    FWIW - my TR3A measures (unladen) 13" on the drivers side and 12" passenger side. Probably about level with big me behind the wheel. Doesn't seem low to me.


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    Senior Member Simmo's Avatar
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    Re: 3A Rear body sag?

    I have a simular problem.
    I have put new springs in and that didn't solve it.
    Put a 3/8 piece of steel under the passengers side spring to lower one side and that helped cheat the situation but it is still drooping about 1/2" on the drivers side. I am thinking that sitting in the garage for many weeks at a time is letting the springs settle and therefore I am noticing the droop much more.
    The body is sound with no rust

  12. #12
    Luke Skywalker
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    Re: 3A Rear body sag?

    With new Moss rear shocks and springs I'm getting 13" on pass side and 12 5/8" on driver's side....this is with the 3/8" plate installed on pass side. I assume anywhere close to that vicinity is pretty much normal.

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