Thanks for reading this. I have a 1976 Dodge class C motorhome with a 2 barrel 360. Milage is 71,000. I was just wondering if I should change out the timing chain and gears now or wait until when? I had a friend who had his slip on a 318 77' Aspen at 90,000. That car though truly had the stuffing beat out of it. How likely are nylon gears to fail with age and not necessarily miles?

 

Welcome. You are correct, age and severe use will wear/damage the timing set.

If you can move the crank back and forth until you feel valve train resistance, it will tell how loose it is. 5 degrees of movement is ok, 10 degrees or more should be changed.