I changed the oil on the weekend and strained the old oil thoroughly. I was looking for tiny pieces of the orange tensioners. I didn't find anything. I used a paint strainer and there was nothing in it when all four liters went through it. I'm hoping that is a good sign as I am thinking of changing them out this winter. 03 RKC with 21,000 miles (34,000 km). Nothing on the magnetic drain plug as well.
Cam chain tensioner material won't stick to a magnet. Cut open the oil filter and look for debris. Better yet...remove the cam cover and inspect the tensioners.
i've got some friends that their cam chain tensioners were shotat 15,000. most went to gear drive, except one guy and he's replaced them twice now in 43,000 miles. early twinkie owners need to keep their eye on them.
Mine were shot at 13000, got lucky ( unlucky) and had an exhaust lifter collapse and when I went in to replace it, noticed orange particles in the oil.
Don't forget that the oil goes through the filter first. I had mine go twice around 32,000, but, that meant the inner was worn to metal and shot to hell. The second time a piece broke off and was laying at the bottom of the cam chest. Never know when these will crap out.
Not to start an oil thread, but using synthetic oil I have seen many sets with over 50,000 before changing. the critical part is regular change with great (your choice) oil.