To check, it must sit level, have oil in the hydraulic tank (left fender, next to the ABS system), and the rear suspension must move easily.
If it is rock hard, the gas spheres are shot, you need new ones (about $90 each, plus installation and a quart of fluid). Check very closely for bad struts, though, if the suspension is hard, because failed gas chambers seriously overloads the seals on the struts, and they can blow out. Not replaceable, so you are out new struts. Crosswind sensitivity and torque steer accompanied by thumps under the back seat are bad links, just like the sedans (and I would plan on having to replace them sooner or later, they go bad). Peter
