Hi Cal:
Cal, I'm really happy that these pads have worked out for you! Hopefully they will last as long as as you have the truck and camper, but if not, it will be easy for you to make new ones.
As many on this forum know, most trucks (not all, but many) are at or over their weight limit carrying a camper and most of us want to go down the road level, so some form of over load springs are usually fitted. Air bags work great on the road, but not so good off road, where they don't do as good a job of controlling rock and roll, but are used by many truck campers because of they are a fairly inexpensive upgrade and pretty easy to install, solving the overload issue for most campers. However, to control suspension movement on challenging road surfaces, overload springs seem to give the best performance. Why go into all of this? Because the overload spring setup Cal has engineered and installed on his truck provides an ideal solution for his rig and how he uses his camper. The only fly in the ointment was that the contact pads that came with the springs didn't last, and without contact pads the overload springs were not very useable. After trying a number of different contact pad materials, I'm really glad Cal has hit upon what appears to be the answer to contact pad requirements. I only suggested that UHMW might be worth a look, it was Cal who designed and built his pads, and it appears he did a fist class job. Terry