Eighty thousand pounds, the federal cap on truck weight that’s observed by many states, is regularly exceeded by heavy-haulers. With proper permits and escorts, they carry large, non-divisible loads such as electrical transformers and construction equipment on hefty lowboy trailers. Gross combination weights often exceed 100,000 or 200,000 pounds. When I see a rig like that, I envy its driver.
Once in a great while I do drive such things, and this Kenworth T880 heavy-haul tractor was almost that kind of experience. Its gross vehicle weight rating exceeded 80K by 2.5 tons. However, my hosts at Kenworth's Chillicothe, Ohio, plant where this tractor was assembled couldn’t arrange a massive load. So we instead pulled a partly loaded van for a GCW of about 56,000 pounds — shucks! But it still gave a hint at how the vehicle performs, which was smoothly, quietly and effortlessly.
It had an Eaton UltraShift automated manual transmission and showed surprisingly good maneuverability in a couple of tight, right-hand turns that suddenly punctuated our otherwise easy cruise on highways north of the plant.
On the Road
Alan Fennimore, Kenworth vocational marketing manager, rode shotgun, and we got to talking while breezing up U.S. 23 and shot right by our turnoff for Ohio 361. But about a half-mile later I spotted a gravelly apron that connected to a crushed-stone road that doubled back toward that state route. I snapped on the blinkers and pressed firmly on the brake pedal, and the air discs on the front and tandem axles slowed us straight and true.
The wheels and tires on the steer axle were wider than what you see on a typical highway tractor, but the setback steer axle aids wheel cut, and the T880’s turning radius was just short enough to make the double right turns without any backing up. And with the autotranny doing the shifting, I needed to worry only about keeping the left-side fender out of the bushes and the 53-foot trailer’s wheels out of the ditch.
Whether on unpaved or paved roads, the T880’s Sheppard dual power steering was precise and the rig was easy to keep in a travel lane, which is not always the case with such steering gear. The 18-speed transmission was programmed to keep a lid on engine revs so the engine stayed unobtrusively quiet. The cab itself is nicely insulated, including triple door seals, so wind noise was low, and Fennimore and I could talk in conversational tones.
Under the hood was a 12.9-liter Paccar MX-13 diesel. This one had the latest 500 horsepower rating — something undreamed of for 788 cubic inches, a displacement we used to call “mid-bore” back when it took true big-bore diesels with 855, 928 or 998 cubes to make that much. So we never lacked for go power on our 50-mile loop, and were back at the factory in less than an hour.
Even though we weren’t heavy-hauling on this trip, the T880 was capable of it, with a GCW rating of 144,000 pounds. Its MX-13 was housed under a moderate-length hood that added up to 116.5 inches from bumper to the back of the cab. This model can also be had with a longer hood and 122.6-inch BBC, which is standard for the optional, larger Cummins ISX15. The standard T880 radiator is more than adequate to cool the engine for this level of heavy-haul service, Fennimore said. Eventually there will be a wide-hood version with a bigger radiator, as there now is with the T800, for extra-heavy, slow-speed duties.
Before we departed, Fennimore walked me around the tractor and pointed out some of its beefy equipment, such as the 20,000-pound steer axle with its big 425-series tires, the liftable pusher axle that’s also rated for 20K, and the fifth wheel sitting on long slider racks. Its frame had 10-3/4-inch-tall frame rails with full inserts, common when pusher axles are used and to take the heavy fifth-wheel loads anticipated in this type of service. He said he’s spec’d even brawnier versions, including one with a GCW rating of 240,000 pounds. It had stronger frame rails and suspensions, among other things.
Heavy hauling is among the many tasks for which the builder’s designers and engineers have outfitted the T880. About 85% of the applications heretofore handled by the venerable T800 can now be taken on by the T880, and more are on the way, Fennimore said.
Though it was introduced last year and only entered production in December, the new model, with its wider, roomier and more comfortable cab, is catching on fast, making converts of truckers long loyal to the “T8,” which has been in production for 28 years.
“A lot of guys still like the T800, but then they get into this and they look around and say, ‘Wow!’” Fennimore said.
The T880’s dash is more automotive in style and houses a lot more electronics, including a driver’s information panel behind the steering wheel and a large multi-function color screen to the right. That displays navigation maps and instructions and other techie stuff, but can also show virtual gauges to provide arcane info like the temperature of the oil in the rear-rear drive axle. This preserves dash-panel “real estate” and renders the old gauges obsolete – assuming that the screen, and the computers that feed info and graphics to it, last as long as the T880 as a whole is likely to.