Rear End Height Help....

Ok, so here are my measurements:

Front driver side - 24 3/4
Front passenger side - 24 3/4
Rear driver side - 27 1/8 (27 when I sit in it and get out)
Rear Passenger side - 27 1/4 (27 1/2 when I sit in it and get out)
(Front does not change once I sit and get out)

When I stand behind the rear of the car when she is parked I notice the driver rear is slightly lower than the passenger rear.... this BUGS me!

I took measurements from the garage floor to the bottom of the rear leaf spring by the shackle and from the trunk floor pan to the ground... both side..... there is a 1/2 difference on the trunk floor, higher on the passenger side. the leaf measurements at the shackle end were the exact same...

So..... besides paying $$$$$$ to "un-tweak" the rear I have rear some posts about using a slightly longer shackle on the low side or adding a lowering block to the high side..... now it seems the consensus is that anything more than 1 inch is not good... I would say mine would need 3/4 of one or the other....

Question is which one is the lesser of two evils?

Thanks for any help! View attachment 108753
 
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You need to look at the rear frame rail inside the tire opening first to see if one rail has a kink ,it will probably be near the bump stop .I there is no kink it is probably not a bent rail and only sagging springs .If it is the springs you could use a spacer to even out the height .I would also check the bushings to see if they are worn .
 
It’s not uncommon for the driver’s side to “droop” more than the passenger side. Most people don’t even notice the difference. This comes from years of extra weight on the driver’s side. It could be the frame rail is just slightly bowed due to that extra weight over the years. Also could be somebody replaced the rear frame rails and got one off slightly from the other. I would start by measuring centerline of the front leaf spring mount hole (of the frame) to the rear centerline of the mount hole (rear frame rail) on both drivers side and pass side to see if there is a difference in length. I'm assuming you did put new bushings in when you changed springs. Then do a few other checks like
Check that you do have the same shackles (length) on each side.
Check that your shackle holes are not worn or rounded out.
Check that you have the same bolt diameters on all shackle bolts.
Check the dia on the front leaf spring bolts as well.
Check that the bolt diameter is the right diameter and fit for the bushing and shackle holes.
Check that your locating pin on your leafs are seated properly and there is no gap between your rear-end spring perch and the spring itself.
If your frame rails are original they are likely weakened some what and aside from replacing them you may have to live with this. If they are old and weak then tweeking them wont last.
The thing you don’t want to do though is add a longer shackle on one side as this changes the geometry of the spring as it compresses.
 
Well I would eliminate the other items I suggested and go from there. Obviously the right thing to do is take it to a frame shop for adjustment (if it is just sagging from time). But the easiest and safest alternative is to shim the rear-end spring perch.
 
How did you tighten the rear end pads ,with weight on the springs or hanging .The car needs full weight on the springs when tightening .If hanging when tightened one side may be loaded more than the other.This applies to the front bushings as well .While the car is setting flat and on a level surface loosen the front leaf bolts ,and the U bolts ,just loose only ,then tighten them again .If they were loaded this will relax them and let them even out .
 
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Not to hijack the thread, but I just noticed the same issue on my 65 coupe and was about to order a new set of leaf springs and hardware. DS sitting lower than PS seems to be a common problem. Great info here.