Like viggy said, every truck is going to be different depending on year, mileage, drivetrain, and how the truck was used. On a newer (say 96+) S10 with a 4.3 and 4wd, by 100,000 miles or so you will probably be replacing the lower intake gaskets, water pump, thermostat, tune-up items (cap, rotor, plugs, possibly wires), fuel pump depending on use, and most of the front suspension wear items (U/L ball joints, idler arm, control arm bushings, wheel bearings). A 2wd would be the same mechanically except for, obviously, the front suspension.
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2000 Chevy Blazer ZR2
Performance Mods: Numerous
Suspension Mods: Some, but not enough
Exterior Mods: Just Right
1987 Buick Turbo T Dark Red
Low 11 sec sleeper
.030 4.1 block, PT6262E, & other odds and ends....
My Cardomain