Somewhere in the country at this very moment, a Chevy or GMC full-size pickup is working for a living--the new Silverados are at the mall, while the stalwart C/K iterations, built for the 1990-1998 model years, are in the field.
Sandwiched between the blocky previous-generation truck and today's sleek Silverado, the C/K series represented the beginning of the full-size truck's gentrification. Introduced in 1988 as an early 1990 model, the first C/K, and its identical GMC brethren, put simple, modern bodywork atop a typical truck chassis, motivated by a selection of generally excellent Bow-Tie powerplants. Early C/Ks (the C designates two-wheel-drive versions, the K is for 4WD models; they were identical in about every other way) came with a choice of a 4.3-liter V-6 or one of three gasoline V-8s (5.0-liter, 5.7-liter, and 7.4-liter).
Three cargo capacities were offered, too; the 1500 is the half-ton, 2500 is the three-quarter ton, and the 3500 is the one-ton. Not all engines were available with all configurations for all years, but there's still an astounding combination of bed lengths (6.5- and 8.0-foot), cabs (standard and extended), and wheelbases (117.5-155.5 inches). Plus, there are several trim levels, from the base work truck through the leather-clad Silverado. All were two-doors until a third semi-door on the passenger side (called the Easy-Access System) was introduced in 1996 on extended cabs. It became a mandatory option on the shortbed 1500 in 1997.
Through the C/K's lifespan, Chevy gradually upgraded the powertrain choices, but a noteworthy jump came in 1996 as the newly christened Vortec engines gained power and civility. We'd skip the V-6 for anything but light-duty work and look instead at the 5.0- or 5.7-liter V-8s; the larger of these packs significantly better grunt, 30 to 50 pound-feet more, depending on model year. Guys with a penchant for burning rubber might want the 7.4-liter engine on the heavy-duty trucks, which had 410 pound-feet of torque at the end. Also available on 2500 and 3500 models are diesels--a naturally aspirated 6.2-liter V-8 in 1994, replaced by a 6.5-liter turbodiesel in 1996 (the better choice).
Trucks live hard lives--and this one lived a long one--so the fact that a list of recalls and scores of Technical Service Bulletins could fill a phone book shouldn't be too daunting. Even so, this was a period when Chevy was working through quality-control issues, so the trucks got progressively better later on. Find one with the options you want, one that hasn't worked the fields for a decade, and you'll get a lot of suburban hay-hauling for the money.