At what mileage do you need to replace the timing chain(belt)? Also, spark plugs @ 100k? Thanks!

 

I don't think that there is any prescribed time to replace the chains. I would only do it if the truck is running very poorly and all other possible problems had been eliminated. The chains should last at least 200k miles. The plugs are supposed to be replaced at or slightly before 100K miles.

 

Buzzard,

Thanks, I appreciate it.

 

One caveat about the plugs..... wait till 100K and they may be tough to do. The local parts guru that I use says a lot of folks have issues with the plugs being frozen in the head at 100K. Not a good thing when the plug has steel threads and the head is aluminum.

I have not (yet) done the plugs in my 98 4.6 (76K), they're sitting in the box on the kitchen counter....so this is not a comment from my own personal experience. I'll know better once I get motivated...