[Fulltiming]

Sounds like you have a significant air leak and/or a leaking air tank if the rig sinks to the bottom fairly quickly. If the valves are holding and your air bags and air tanks are sound, you should be able to go for days or weeks without the rig sinking to the ground. The valves are the most common source of leak down. Really sounds more like an air issue than an HWH issue. The slides sounds like an alignment issue. Rolling a seal should be a very rare occurrence, certainly not 3 times in 80 uses or even in 800 uses.