By Paul Abelson
senior technical editor
After a 20-year reign as one of the most highly desired tractors among owner-operators, Peterbilt’s 379 is going out of production. Once the 1,000 Legacy Class 379s are sold, it will no longer be made.
Unless you’re an absolute purist, you’ll probably appreciate its replacement, the 389. Based on the same narrow cab, with its flat glass, split windshield – which is easier and cheaper than one-piece curved glass to replace – the 389 looks a great deal like its predecessor, at least until you get up close.
With a closer look, you notice that the square radiator shell has rounded corners and edges, as does the larger chrome bumper. The cab air shield was optimized to work with the new contours. The headlights, mounted in the traditional location on the radiator shell, are state-of-the-art projection low beams with prismatic reflector halogen high beams. The lamps are combined with LED side-turn indicators, all packaged in aerodynamic shells.
All these improvements lower coefficient of drag about 4 percent, more than enough to overcome the 1-percent loss of fuel efficiency with ultra-low sulfur diesel.
The standard hood length for the 389 is 131 inches, 4 inches more than the 379.
At the 389’s introduction at the 2005 Mid-America Trucking Show, Peterbilt claimed a 226-percent improvement in forward lighting.
The night before my scheduled test drive, I arrived in Denton, TX, at Peterbilt’s factory. I asked if I could do a side-by-side headlight comparison. We lined up a 379 and 389 side by side about 150 feet from a blank factory wall. I can’t vouch for the percentage, but the 389’s beams were noticeably wider, significantly brighter and higher to the right. When I drove the new Pete through open fields, I found more light aimed right where it was needed.
The next day, I checked out the cab and sleeper. The Unibilt 70-inch sleeper with platinum interior was loaded with useable storage. Under the passenger-side TV shelf and storage shelf, a pullout worktable sat above two deep slide-out bins. If you fill up the four – two rear, one each side – latching bins above the bunk and the netted cubby holes above, you can use the covered bins as storage. If not, they make great file folder drawers.
Behind the driver, the fridge sits above the hanging closet. Interior lighting is excellent. In addition to the fluorescent dome lamp in the sleeper, two directional flood lights are in the ceiling, and there’s a flood light at the driver’s feet. For reading in bed, there are two swiveling lamps, one over each shoulder. They’re the same type as those in the cab for map reading or working on logs.
My test drive sat on a 273-inch wheelbase. The 18,370-pound tractor had Bridgestone 295/75R22.5 tires on Alcoa Dura-Bright wheels. The 2007 Cummins ISX churned out 550 horsepower at 1,800 rpm, with 1,850 lbs.-ft. of torque at 1,200 rpm. With the 3.70 drive axle ratio, it stayed just under 1,500 rpm at a comfortable 66 mph cruise speed.
With all its torque, it took the 77,400 pounds up most southern Oklahoma grades with minimal drop off in truck speed. In 18th, speed fell from 66 mph to about 62 or 63. When I split to 17th, still under 1,800 rpm, it held with no speed loss.
The 389’s road manners were impeccable. Its air suspension absorbed most road roughness. When there was no traffic around me, I simulated a sudden lane change maneuver. The body roll transitions were smooth and the truck remained controllable.
If you’ve ever visited Peterbilt from the north, you may remember Exit 468, the one that starts with a gentle curve, then has a sudden dog leg. I entered it as I would any ramp, and then noticed the curves. My bad, but Peterbilt good! The Bendix front disc brakes brought the truck down to a safe speed quickly, with no side-to-side pull at all.
In Oklahoma, I had an opportunity to maneuver around several sharp corners on two-lane roads. With a 53-foot box full of concrete ballast and a 273-inch wheelbase, it took every degree of the 50-degree wheel cut and every inch of the road and shoulder to turn 110 degrees. The Pete made it without requiring any backing, but just barely.
The new dashboard was attractive and practical, with easy-to-read digital readouts in the driver information panel. The UltraRide Hi-back seats had leather seating surfaces. I would have preferred arm rests on both sides, not just on driver’s right, passenger’s left. With one elbow at elbow height and the other on the window ledge, I find my back skewed left, and any jarring twisted my spine. This, by the way, is not unique to Peterbilt. I find it with any truck with just one driver’s seat armrest.
I’m generally a fan of aerodynamic trucks, because I see trucking as a business. My preference is for the better fuel economy and performance offered by the new aerodynamic 387 over the 389, all other things being equal. But if classic-looking trucks with modern flair are for you, I can’t think of a better truck than the 389.
This is about as good as a classic truck gets. Look at it as the 379 brought up to 21st-century standards.
Paul Abelson may be reached at firstname.lastname@example.org.