The 2004 GMC Sierra 3500 represents the first model of the second generation, standing as a heavy-duty full-size pickup truck. It is offered in both RWD and 4WD drivetrains with a four-speed automatic or a five-speed manual transmission. This workhorse features a powerful 8.1L, V8 engine that produces up to 300 horsepower, or a Duramax 6.6L, V8 turbo diesel with a notable 365 lb-ft or 620 lb-ft of torque. The Sierra 3500 comes in either a single-rear-wheel (SRW) or dual-rear-wheel (DRW) (dually) configuration. Inside, the base trim offers basic amenities while higher trims like the SLT add leather upholstery, power and heated front seats, and automatic climate control. Though not heavily packed with technology, the 2004 Sierra 3500 emphasizes hard work and durability.