The next generation

This test-drive T660 featured an 86-inch Studio Aerocab sleeper with Pendleton interior.

Kenworth’s T660 is the latest incarnation of the company’s first aerodynamic truck, the T600. With an optional APU and enhanced aerodynamics, the T660 sets you up to save money, and the comfortably appointed interior lets you do it in style, the company says.

To find out for myself how it measured up, I test-drove two differently spec’d T660s at Paccar’s Technology Center in Fredonia, Wash.

As snow started falling, I climbed into my first test-drive: a silver pearl T660 Aerocab with an 86-inch sleeper. Natural light from sleeper windows and the T660’s sunroof added to the Pendleton interior’s relaxing affect, even on a cloudy day.

The Pendleton interior styling and studio-sleeper room are eye catching. Wood-grain dash panels, slate-gray, diamond-tufted carpet and brown upholstery look refined yet sturdy. The seats, with numerous electric and manual controls, are heated, and when vertical, the armrests fold behind the seat backs for a wider walkway.

The package includes a refrigerator installed under-counter, television hookup and room for a microwave and coffee machine. It also has stainless steel lights, AM/FM stereo CD player with MP3 and Sirius capabilities, dash-mounted global positioning system, quiet-cab insulation and remote, keyless door locks.

The 86 inches of sleeper promise comfort, whether parked or rolling with a team. My 76-inch frame was comfortable stretched out east-west or north-south, with room to spare. The sofa bed has twice a single bunk’s width: just big enough for two, and there’s a folding upper bunk, too. Both bunks have clock, light and temperature controls.

There’s plenty of smart-looking cabinet and under-bunk storage, and the big shelves on both sides, up high with three-inch retaining risers, are particularly roomy, secure and convenient. The sleeper windows double as emergency exits, and snow won’t come through the open sunroof while you’re rolling.

This interior more resembles that of a comfy motor home than a traditional truck, but functionally the cab shows Kenworth’s heavy-duty experience. Dash gauges are numerous but organized, easy to read and more reliable (the company has simplified its dash wiring). A multifunction digital display provides on-board diagnostics, fuel mileage and also a gear display: handy with an automatic transmission. Driver storage compartments are secure and accessible, the adjustable steering column has a position for every driver, and dash controls, including the GPS, are within an easy arm’s reach.

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The T660’s sloped, aerodynamic hood is computer-designed to reduce drag, increase fuel mileage and increase visibility. Under the test truck’s hood was a 475-horsepower Caterpillar C15 with 1,650 lb.-ft. torque hooked to an Eaton 13-speed Ultrashift fully automatic transmission and leading to 3.55 Dana DSP40 drive axles and Bridgestone 295/75R22.5 tires. It had a concrete-block payload and weighed about 80,000 pounds.

The test-drive’s first leg followed Kenworth’s suggested route: state Highway 20 east to I-5 and south to exit 215; then back north to exit 221 and down two-lane country roads back to Highway 20. The second leg was west on 20 to Oak Harbor and back again.

I was southbound on I-5 when the snow reduced visibility to less than 100 feet. But the roads were too warm to freeze and the test rig was heavy, so I continued south well below the speed limit.

Turning around at exit 215, I overshot the left turn onto the northbound entrance ramp by a few feet. While swinging onto the ramp I found that the T660 cuts a sharp turn if necessary. After a stop on the ramp shoulder for a map check, I drove north and got off at the 221. Following the route, I turned left under the interstate and promptly missed a turn that wasn’t on the map and headed south instead of north on a shoulderless, two-lane country road.

With no turnaround opportunities in sight and no driver’s road atlas, I wound up westbound on state highway 532 en route to Camano Island State Park. The snow had tapered off, but tourist traffic was thickening, and parking lot after parking lot was too full for a U-turn.
Finally, a mostly empty country club parking lot appeared on the left. The T660 politely idled in, smartly pivoted 180 degrees on the trailer tandems and rolled back out onto 532.

When you miss a turn, it helps to be in a truck with a defroster that melts snow off the windshield; good wipers and mirror heaters for maximum visibility; sure-footed maneuverability in close quarters, especially when fully loaded; responsiveness in suburban traffic; and a turning radius that allows tight U-turns.

My next highway test-drive was also a silver pearl T660, but with a 72-inch sleeper and a 500-horsepower Cummins ISX with 1,650 lb.-ft. torque and coupled with an Eaton 14-speed Ultrashift. The route was much shorter: west on Highway 20 over Deception Pass – a narrow two-lane bridge with sharp curves at both ends – and down to Oak Harbor for a U-turn and the drive back.

This T660 had Kenworth’s Clean Power auxiliary power system, introduced in March at the Mid-America Trucking Show.

Kenworth powers the system with four deep-cycle batteries, anticipating Environmental Protection Agency regulation of exhaust from diesel- or gas-burning APUs, says Kenworth’s Advanced Technology Manager John Duffy, one of the APU’s designers. Most fossil fuel APUs use about a half-gallon of fuel an hour, but Kenworth’s Clean Power uses none, maximizing fuel savings.

Clean Power is mounted beneath the bunk and has a simple design: a fan and cooling coils.

Duffy says it can cool the sleeper to 75 degrees for up to 10 hours, even with a television, refrigerator and coffee maker in use. Both the lower and upper folding bunks have Clean Power controls. Cut-off switches prevent it from draining power from the batteries, which recharge to full strength when the engine is running.

To maximize efficiency, Kenworth insulated the cab and replaced standard interior incandescent bulbs with power-saving LEDs: a first in the industry, Duffy says.


T660 “Pendleton” Specs
Tractor: Kenworth T660 86-Inch Studio Aerocab w/ Pendleton Interior
Engine: 2007 Caterpillar C15 475 hp 1,650 lb.-ft. torque
Transmission: Eaton 13-speed Ultrashift
Drive Axle: Dana DSP40
Axle Ratio: 3.55 – 1
Front Axle: Dana Spicer E-1202I
Front Suspension: Taper leaf w/ shock absorbers
Rear Suspension: Kenworth AG380 52-inch spread
Front Brakes: Bendix Air Disc
Rear Brakes: Bendix ES S-Cam 16.5 X 7 dual
Front Tires: Bridgestone R287 295/75R22.5
Rear Tires: Bridgestone M720FE 295/75R22.5
Batteries: PACCAR 2800cca dual purpose
Alternator: PACCAR brushless 130-amp
Starter: PACCAR 105P 12-volt
Compressor: Caterpillar 270 16.1 cubic feet per minute
Exhaust: Diesel particulate filter & single, vertical 54-inch chrome tailpipe
Fuel Tanks: 120-gallon polished aluminum
Paint: Silver Pearl
Wheelbase: 240 inches