Rear shock psi?

[anlauto]

That's a great example ....we need to keep those pictures on file

[dodj]

Those air shocks must have been extremely popular back in the day. Mine had normal shocks on it when I got it, but there was a schrader valve mounted in the trunk and a bit of tubing underneath. 

It also had the rear valance missing and 5" or 6" 'clam digger' shackles out back to keep the bum up.

[MoparLeo]

Shock absorbers do not support weight. The spring does. What a "shock absorber" actually does is to dampen spring action. The more proper name, used in Europe are dampers.
They try to keep the tire in constant contact with the road surface.
Gas shocks use a different internal system to separate the fluid chambers with a gas bladder. The purpose is to eliminate foaming of the fluid during rapid compression/rebound cycles. Not to support any kind of weight.
Air shocks are actually "air assist" shocks . Air bags have been used for Trucks for many years. The mounting system on trucks is built to a different standard than a passenger car.
As said before, it was a cheap/simple way to raise the rear of the car starting back in the 70's. Was never a good idea, more of a fad.