The wdc telescopes in my KH & pup are ten yrs old, dumped hundreds of loads with the trk, not so much with the pup and both continue to work well today. The telescopes seem to "sweat" a little bit, there's oily grime at the base of each one, but since filling the 110cc custom made reservior ten yrs ago, I have never added oil & they always lift to the top.
On the other hand, it seems wdc's quality has turned to shyt!!! in recent yrs, problems with everything they put on the market... what have they done differently lately? Using poorer grade materials to cut costs & increase profit margins?!