The 150,000 mile mark is coming soon for me, and I'm trying to get a list of things that I need to do (and what I don't need to do). The truck runs fine, but I know it needs some attention.

I've had the car since 118k, and I changed the timing belt, pulleys, water pump, air filter (K&N), and fuel filter when I got it. Up to this point, that's all of the major maintenance that I've done to the truck. The plug wires (and possibly plugs?) are original, as the manufacture date still says 1997 on them. Is this one of those "if it ain't broke don't fix it" kind of situations? It either sparks or it doesn't, and I'm sure a misfire is fairly noticeable, but I'm definitely not opposed to changing them if it's necessary.

Next I want to do a tranny flush and differential oil change, and I'm sure it's been a long time since these have been done.

Of course I'll clean the K&N and MAF sensor, and maybe do the deckplate mod while I'm at it.

Another thing I'm up in the air on, whether or not to do a top end clean. It sounds like GM's top-end cleaner is a better option than Seafoam, but I'm yet to find a definite set of instructions as to how to do the cleanup... Seems like sucking it in thru the PCV then killing it and letting it sit for a couple hours is the trick?

Anything I'm missing? Any input is appreciated. Thanks.