I've got an annoying tick in the bottom end of my 85 22R. It sounds like a valve tick, but I've checked them and adjusted them twice now just in case, and the timing chain guides looked great when I put my new head on +-2500 miles ago. As far as I know the bottom end has the same 253,3** miles the truck has (PO told me it was rebuilt 70k before I bought it, which was a lie). I can't see how the timing chain would have all the sudden gone FUBAR over the course of 2500 miles, when it showed no sign of being stretched to the point of being a problem the last time the motor was cracked? Any other guesses? It does seem to get better (or at least I can't hear it) anywhere above idle.