Thanks for the welcome...

Injectors were done last may and I saw next to no change in performance/fuel mileage etc.
I had new nozzles put in and the crack pressure reset to whatever the shop knew as std.

This might help explain my concern for the engine rings.
another symptom I know the problem to is at cold start (below 0°C). my glow plug controller does not operate after starting the engine causing it to smoke (white/grey, not steam) and miss on cylinders until warm enough. I have a manual glowplug switch and can play with that to keep it happy for a couple minutes. But before I put the switch in, the truck would smoke and miss enough to sometimes stall out completely (even with 5W40 syn).