Once seen as plain, dowdy, and uninspired, the Frontier made a useful jump in practical features.
By the 1990s, Nissan, the company that (under the Datsun name) essentially created the compact pickup market in the U.S., looked to be falling behind the times. That was until 1998, when the Frontier made its debut. The previous truck, which didn't actually have a name, had been around since 1984 with only minor changes.
In place of the chunky model 720 pickup, the Frontier arrived in a slimmer, simpler shape that some called plain, dowdy, uninspired. Regardless, the vehicle was larger in just about every dimension: The regular-cab model was almost 10 inches longer and the King Cab was longer by another half foot. It was also, in some critical ways, a useful jump in features--a new double-walled bed, for example--and refinement far surpassed that of the utilitarian, nameless pickup. Likewise, the interior was much more driver-friendly than the boxlike cage it replaced.
For the first model year, only the carryover 2.4-liter four-cylinder was available, but, the next year, Nissan dropped the Pathfinder's 3.3-liter V-6 into the engine bay. Not only was the six-cylinder engine 27 horsepower up on the four-banger, but it had a lot more torque. On the used market, the V-6 is more common because it's more desirable. (The regular-cab model only had the four; look for a King Cab or larger for the six.)
Power-mongers should seek the SC model, which first came out in 2001. The basic 3.3-liter V-6 received a Roots-type supercharger for an impressive 210 horsepower and an equally useful 231 pound-feet of torque. Note, however, that the SC is available only with the four-speed automatic. (If you want the supercharged V-6/manual transmission combination, your only choice is the rare Desert Runner model.) The normally aspirated V-6 and the four could be had with a five-speed manual in addition to an automatic, and any six-cylinder iteration could be had with four-wheel drive. Owners complain about mediocre mile-age with the SC, which is understandable, considering how these trucks are probably driven.
Until the 2000 model year, cab choices were limited to small (regular cab) and somewhat less small (King Cab). It's worth noting, Nissan never created a rear-hinged third or fourth door for the King Cab model; get used to slinging your gear over the seats. A four-door Crew Cab came out in 2000, offering four front-hinged doors and a modest rear cabin suitable for kids and small adults. The additional room of the crew cab came at the expense of bed length: King and Crew Cab models had the same wheelbase, so the bed shrank to 56 inches to accommodate the crew cab.