My 1984 Mercury Grand Marquis rides on an uneven keel
The rear of my Grand Marquis has been leaning downward to the left (approx 1.5 inches) since I bought it. At first, I attributed the list to the usual slant roads have to have so rainwater can flow off. That wasn't the case, however.
My next guess was that the 30 year old springs may simply have become soft with age, so I had all of them replaced (front and rear) with OEM specification Moog coils and installed new shock absorbers, too, (and what a good idea that was since the old ones were suffering a bad case of rustout).
The new springs and shocks have made the Merc ride and handle wonderfully comfortable again, but the list is still there. I had the frame checked, too, but it's not bent or otherwise deformed.
A member of the community has kindly suggested that the lean may simply be an optical illusion, but my tape measure check doesn't bear it out, unfortunately. The Merc's left rear side sits almost exactly 3 centimeters lower than the right - or the right side is 3 centimeters too high above the ground, which seems likelier the more I look at the car.
So, I'm still puzzled and in search of ideas. Thanks a million.