2020 Peterbilt Trucks For Sale

The most common 2020 Peterbilt trucks on the used market typically include the Peterbilt 579 for over-the-road freight and the Peterbilt 337 for medium-duty vocational work. The 579 is a conventional highway tractor often spec'd with a sleeper, PACCAR MX-13 engine, aerodynamic bodywork, and air ride suspension. The 337 is a versatile medium-duty platform used for rollback tow trucks, box trucks, service bodies, and other upfits where a 26,000 GVWR or similar Class 6 to Class 7 configuration is important.

Start with the powertrain specification and service history. On a 2020 Peterbilt 579, buyers usually focus on the PACCAR MX-13 engine, transmission type, rear axle ratio, wheelbase, and sleeper configuration because those specs directly affect fuel economy, drivability, and resale. It is also important to review aftertreatment maintenance, fault code history, DOT inspection status, tire and brake condition, and the operation of cab electronics, air ride components, and the sliding fifth wheel if equipped.

A 2020 Peterbilt 337 is a well-known choice for rollback and light-duty wrecker applications because it combines a durable medium-duty chassis with good cab visibility and strong upfit compatibility. Many are equipped with a Cummins 6.7L or PACCAR PX-7 engine, Allison automatic transmission, air brakes, and either spring or air ride suspension depending on the intended duty cycle. Buyers should verify bed manufacturer, deck length and width, wheel lift rating, winch capacity, front and rear axle ratings, and actual remaining payload once the body and accessories are installed.

The right choice comes down to route profile and body application. A 2020 Peterbilt highway tractor such as a 579 is built around fuel-efficient highway miles, driver comfort, and sleeper or day cab configurations for freight hauling. A 2020 Peterbilt vocational truck such as a 337 is built around PTO capability, tighter wheelbase options, body-builder friendliness, and ratings that support tow bodies, tanks, utility bodies, and other specialized equipment. Buyers should match engine, transmission, axle capacity, suspension, and cab style to the actual work instead of buying by appearance alone.