[Fulltiming]

David, I have driven a couple of early 1990 coaches that had the air leveler AND HWH hydraulic jacks. The factory did this at the owners request but is the exception rather than the rule. I would not want to get under a coach supported by built-in hydraulic jacks either. The safest answer to to add large wood cripping or use industrial grade jack stands that are adequately weight rated to support the weight.