If is not the air ride suspension then it would likely be Safari's rubber torsion suspension system, which would concern me, as I don't know if replacement rubber parts are still available for it. Given its age I suspect any original rubber suspension components would be shot, the replacements may even be shot by now as most rubber suspension components have a life of 12-15 years at best.
2002 Safari Trek 2830 on P32 Chassis with 8.1L w/ 400 watts solar 420Ah LiFePo4
2017 Jeep Cherokee Overland & 2007 Toyota Yaris TOADs with Even Brake,
Demco Commander tow bar and Blue Ox / Roadmaster base plates