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71 Cutlass rear not level

Full frame off restoration is coming to an end but can not figure out why the car rear does not sit level. New rear end from moser, replaced frame, new springs and shocks. Want to figure this out before paint. Any other ideas?

Which side is sitting higher?

My first guess is that the new springs don’t match. You could switch them side to side and see.

I’d take a number of measurements to see if something in the body or frame is off.

I agree with texases, replaced frame with what?

I’ll cut to the chase- if you’ve checked and re-checked everything, then look to the front suspension. BTDTBTTS. Spent quite a while chasing down similar problem on a '71 Chevelle. Finally it dawned on me, check the front suspension. One tire has 3" clearance to the WW, the other 2". The effect is magnified at the rear end.

A frame in better shape then the one I had.

passenger side is high

Did all that already.

What was the problem with the front suspension? What did you do to fix it?

Please list what you’ve checked so far, it’ll help figure out the problem.

In my case, the left upper control arm was binding up. Straining my memory here a bit because it’s been a number years ago now but I had done a fairly extensive restification to it a few years prior. Then, after removing the rear axle and installing an Art Morrison package (tubular arms, adjustable pinion angle, anti-hop bars etc) along with custom progressive rate springs and some other do-dads, I noticed it didn’t sit level anymore. Lots of head scratching, measuring frame heights/axle position, taking parts back off and re-installing but no joy. Finally came to the conclusion it must be in front. Sure enough, even though the bushings were relatively new, the left side upper arm was binding up big time. Full set of new poly-graphite bushings (new springs, shocks etc while in there) and problem solved.

Since you’ve just done a frame off and likely installed new bushings it might not be the same issue. But having wrestled with this same conundrum myself, thought I’d pass along the lesson learned.

Measured frame front and rear. Looks good. Thought it was bad bracket or spring mount on the rear. Measured and checked both on brand new Moser 12 bolt rear. All fine. Switched brand new springs and shocks from one side to the other. Fine. Then turned attention to the front suspension. All new poly bushings, installed 2 new sets of springs to no avail. The driver front spring does look crooked when compared to the passenger side. The driverside swaybar endlinks are touching the control arm but not on the passengerside.

It seems simple but evidently is not. It may be that the shocks are dependent on the sheet metal of the trunk, and rust or weakness has allowed a failure. I had a 72 nova we had to weld a structural plate to the body of the car, Not sure if it applies to your vehicle, but just a thought.

Kind of odd about the front swaybar. Have you disconnected it to see if something is causing a problem? The links shouldn’t be touching the control arm.

Who r&r’d the control arm bushings? I had a shop bend a perfect set from a 69 vette and never said a word about any trouble. Fortunately I noticed it before installing. Easy to tweak them if not careful. Did you check them?