MEDIUM DUTY - Model 330 Trouble-free Operation, Ownership The bumper, grille and sunvisor are all classic Peterbilt touches, but their real beauty is their outstanding durability. The Model 330 is available with either air or hydraulic brakes, giving you a powerful workhorse that can be driven without a CDL. The PACCAR PX-6 engine offers high horsepower and torque plus outstanding fuel economy for greater overall performance. The Model 330 gives you plenty of options. It can be configured up to 26,000 lbs. to meet the demands of any medium duty application.