Jack & Cathy Carson wrote:

Does anyone know whether it is harmful to the Freightliner XC air suspension to raise the coach with the leveling jacks while the suspension is inflated? I plan to install a steering stabilizer and it would be nice to have an additional three inches of space to work under the coach. Thanks.

however make double sure you have a safety system in place to guard against possible failure of the leveling system while working on the coach.

The air suspension deflates over time with the engine off. It takes a few hours but the end result is the same as manually deflating the suspension. If you do use blocks under the tires without the jacks down be sure that anything you take under the coach with you (including you) won't get jammed or crushed when the coach lowers. A good test is to put the coach on blocks with jacks retracted and then dump the suspension and see what room you really have.