I believe there is some mis information in the above strings. The air suspension is designed to keep the rear of the vehicle at the same height regardless of the load. If you add weight in the rear, (passengers, or luggage in rear, add tongue weight) the compressor comes on to raise the vehicle to the "nominal height" if you take that load out of the vehicle and didn't release some air pressure the rear would go even higher. So a valve opens and releases air until the body lowers to the "nominal height". There can be time delays, and suspension frictions so the driving includes those variances. The compressor is a low volume displacement type, and will wear out quickly if allowed to run more than the short periods to retrim the vehicle. Any leak usually wears the compressor, and even if it will run, it does not mean it will generate the pressures needed to "lift the rear" The actual rear height can be adjusted 1 of 2 ways. slotting the variable resister mounting holes to rotate it or changing the length of the little link that goes between the resister and the body or axle (don't remember which now) but you can remove the link and manually rotate the link arm of the resister and with the engine running the vehicle will raise or lower depending which way you rotate it. At least you and see how the vehicle looks for trim and fine tune from there.