Highway miles vers City miles

I have a 2000 Silverado with 66,000 miles in it. I use it to travel to and from work about 60 miles round trip. I am concerned about the miles I rack up. Everyone tells me (OH there Highway miles dont worry). I do maintain the truck 100% from top to bottom. What my confussion is, what is the theory behind the highway, city miles and the break down if any like....(30,000 city equals 60,000 highway) and how long should I get out of my Silverado.

I have wrestled with that debate, as well, as my 99 has 88k on it, almost all of it interstate highway miles; but I now believe I can squeeze out at least that many miles again, or more, by continuing to maintain the truck like I have in the past.

The engine oil and filter are changed every 3k miles, and I have changed the tranny fluid and the rear end oil at least once. The used oils were free of any solid particles and the transmission pan was perfectly clean.

The truck runs strong and idles smoothly. The ignition parts are the originals. Even the brakes are original and still in very good shape. The throttle body gets an occasional cleaning and fuel injector cleaner additives are used every once in a while. A recent OBDII check shows no stored codes.

The only moving part requiring replacement has been the water pump, a simple repair, which replaced the long life (another debate) anti-freeze.

What might I anticipate needing down the road? Perhaps an alternator, maybe a u-joint replacement or a power steering related repair, and I'm betting not much else.

I think the easiest way to look at it is: On the highway your running at a constant pace. Where as, in the city is a constant stop and go(i.e. more wear and tear on the vehicle). :2cents:

Just another thought.... I live in The Phila. PA area.... and I sware by all of the synthetic's lubes on the market. I use only mobil 1 engine oil...however I've been looking at royle purple. As long it's FULLY SYNTHETIC you can't go wrong only draw back is the price. However for new vechicles make sure you follow the mfg. recommended break in period. I started using in my cars/truck at the 4/5k mile oil change. I change my engine oil every 6 months since that only intales approx. 2500/3000 miles. for older cars/truck I would suggest the "blends"... they are a lot cheaper.
I never had a vechicle that left me walking ...or did no go 100K as long as you follow the mfg. maint. requirements.