Rear leaf spring questions


New Member
Dec 4, 2023
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Edmonton Alberta Canada
I have purchased a old set of rear leaf springs out of a 67 Newport.
I plan on rebuilding them and installing into my 67 300 convertible.
The ones in the car now have added leaves installed in the early 70"s when my Dad was pulling a holiday trailer.
The *** end of the car sits a little too high.
The pair i got out of the Newport have different part #s 2539745 & 2539746 .
I cannot see any difference at all between the two sides even the shackles are identical. if any which side goes where.
Other question is being a convertible would it have different springs because the car is heavier?
According to the FSM, the right springs (no matter the model) had an extra 1/2 leaf or so on the rh side to better resist acceleration torque. I believe the base Newports (383 2bbl cars) usually had the lightest/softest springs, where as the 4bbl cars had mid-range heavier springs and sometimes the full normal HD springs. All of which will be detailed in the FSM's rear spring section.

The pair i got out of the Newport have different part #s 2539745 & 2539746
When given two part numbers for a left and right application, the odd part number is the driver side.

I remember this by "you must be a little odd to drive one of these cars".
The factory 7 leaf springs didn't "ride like a truck", but then a friend had a Hemi-suspension 71 'Cuda 383 and it rode just as well as our then-new '72 Newport Custom on the road and better on rough roads. All in the suspension calibrations.