It’s quiet! That’s my prime impression of International’s recently introduced LT series tractor after an autumn press event at the Navistar Proving Grounds in Indiana. I drove three LT625s around a 3-mile paved track.
Quietness is engineered into the evolutionary LT (for Linehaul Transport) series, which is based on the ProStar that Navistar will soon phase out. Noise is muted by effective sound-deadening insulation, particularly door sealing. Consequently, wind and road noise are all but gone.
That was true for two of the tractors, anyway. The third was plagued by constant squeaks. Turned out it did not have grease on the hood pucks, Navistar told us later. That made it squeak badly. Once that was addressed — after I had driven it — the squeaking stopped, Navistar said.
However, this truck had the sole manual transmission among the trio, and my preoccupation with shifting delayed my noticing the interior noise. The transmission was an Eaton Fuller 18-speed that was a joy to operate. Out on the track, I slowed several times so I could downshift and go back up the ratio ladder, often using the thumb switch to split the main gears, just for the fun of it. This is seldom the case with manual gearboxes in contemporary heavy trucks, so kudos to Navistar engineers for that.
In the other two tractors, Eaton UltraShift Plus 10-speed automated transmissions worked flawlessly. The tractors’ 14.9L Cummins X15 diesels, standard on long-nose LTs, were good partners, with strong power and torque unobtrusively interrupted by very smooth shifts. A new, compact column-mounted selector controls self-shifting transmissions; it was simple and easy to use, and also operates the engine brake.
The new interior trim is attractive if muted in color. New instruments have highly legible white-on-black lettering, and switch labels are laser-etched so they won’t wear away, Navistar says. Controls were all within easy reach, and a glance into the roomy sleeper areas showed nicely thought-out storage compartments and comfortable-looking bunks. All designs used ideas gathered at focus groups and in conversations with real-life drivers, Navistar executives said in announcing and launching the LT series just weeks before this demo.
Climbing inside to enjoy the interior amenities is rather easy with an LT, which has wide steps and well-placed (for the most part) grab handles. It’s especially easy for the passenger, who has a stout grab handle mounted on the A-pillar. The driver doesn’t and there’s no option for one, but the doors’ pockets are strong enough to act as handles, and of course the driver has the steering wheel to grasp while getting in.
Navistar says this is a real driver’s truck, and all things considered, I must agree.