1999 Peterbilt 378. CAT 3406E. 15 Speed Transmission. 44,000LB Full Locking Rears. Steerable Air Lift Axle. Only 858,000 Original Miles. Double Framed. Air Trac Suspension. Dual Line Wet Kit. Loaded Interior. Gauge Package. Long Track Air Slide Fifth Wheel. 11R24.5 Tires. Engine Brake. Cruise Control. Dual Stacks. Dual Breathers. Clean Peterbilt 378