The three-quarter ton version of the GMC Sierra received a substantial reengineering for the 1999 model year. Constructed on a brand-new GMT800 platform featuring a strong but lightweight hydroformed frame, magnesium crossbeam and dust resistant steel panels, the 1999 GMC New Sierra 2500 was upgraded for greater work performance. The New Sierra 2500 was offered with a regular cab model as well as an extended cab variant featuring a standard third door for easy rear passenger entry.
Engine power for the new GMC three-quarter ton pickup truck came from a pair of refined Vortec V-8 powerplants. A 5.3-liter V-8 producing 270 horsepower and 315 pound-feet of torque served as the base engine for the New Sierra 2500. The optional propulsion choice for the 1999 GMC New Sierra 2500 is a 6.0-liter Vortec V-8 engine generating 300 horsepower and 355 pound-feet of torque. Available with rear-wheel drive or four-wheel drive, the GMC New Sierra 2500 could be equipped with a heavy-duty rated five-speed manual transmission or two types of automatic gearboxes.
Equipped with the 6.0-liter V-8 engine, the GMC New Sierra 2500 can tow up to 10,500 pounds. Standard features found on the 1999 GMC New Sierra 2500 included 16-inch wheels mounted to an eight-bolt hub, four-wheel disc brakes with anti-lock braking system, dual front airbags and tilt adjustable steering wheel. Remote keyless entry, leather seating, air conditioning and cruise control were optional equipment. Referred to as the New Sierra 2500 for the 1999 and 2000 model year of production, the new vehicle was sold alongside GMC’s previous generation three-quarter ton truck. For the 2001 model year, a regular 2500 model and a new 2500HD version of the GMC Sierra reclassified the work truck line.