2004, bought a 2002 Silverado extended cab 4x4 dually with the 8.1l Vortec engine and the Allison transmission, fully loaded and I paid $31,000 for it, had low low miles.
I actually met the previous owner and he loved it but it did have terrible gas mileage. Ever since I have never gone past 2000 miles on an oil change, 1500 in the winter, I use Rotella T 5-40 full synthetic, in the winter I mix a quart of Amsoil 5-20 and a shot of Marvel Mystery lube, for the Alaska winter cold temps.
I am on the third windshield, third set of tires, replaced all the headlights, fog lights and even a pair of Hella passing lights with HID units, every other light except for some sealed units are now LED, has cadillac outside auto tint mirrors and instrument cluster, and a lot of other little extras from the sound system to stainless hood protectors.
Best truck I have ever owned. Its still a gas hog but I just don’t jump on the throttle much, it actually hardly ever gets past 2500 rpm what with 496 cubic inches and 360 hp. Body won’t rust, first GM truck I have ever owned that will not rust. Its a keeper.
I much prefer my 79 5.7 chevy pickup and my 99 7.3 chevy diesel van, especially since I don’t have to do emmisions. My 2003 4.3 chevy work van, not so much. No power & emmisions sock. Thankfully Texas has lower gas/deisel prices but things in the country are far away.