When should I change my timing chain?

[PKRWUD]

I'm sorry, guys, but I totally disagree. A timing chain has measurable wear after less than 5k miles. Stock or built, babied or trashed, any 5.0 will have a noticible improvement by changing the timing set at 100k miles. I've always done my vehicles at 75k miles, or any time the gears are exposed (kinda like installing a new clutch every time the tranny is out).

An engine may run for 300k miles or more on the original chain and gears, but why? It could go that long on the original plugs, too, but again, why?

Easy, cheap job, with good results.

I say change it no later than 100k miles.

Take care,
ÅChris