Timing chain replacement?
 

Hi everyone. I am approaching 107k on this original 98 4.3L. I realize timing BELTS have to be replaced at a certain mileage (my mom has a Toyota product (she gets pissed when I call it the "riceburner". Piece of crap. Not only with the Toyota recalls, but the metal is so thin that the car wash left a crease in the metal.) that has around 80k and the dealer replaced the timing belt recently.), but what about the timing CHAINS on these 4.3L? Is there a required replacement mileage to prevent it from failing and destroying the engine?

Im honestly not sure,Ive always tested it this way on the older blazers. Pop off the distributor cap so you can see the rotor,then turn the crank back and forth with a breaker bar/extension/socket and see how much play it takes for the rotor to react.

best thing to do is next time the trucks at a mechanic is make them check it

a friend of mine checked it the last time they worked on my truck