Checking out Isuzu's 2008 N-Series trucks

Aug. 1, 2007
ISUZU TRUCK'S 2008 N/W Series of low cab forward (LCF) medium duty trucks are all new, with significant enhancements, including larger cabs, superior

ISUZU TRUCK'S 2008 N/W Series of low cab forward (LCF) medium duty trucks are all new, with significant enhancements, including larger cabs, superior safety, and increased engine power with technology to meet the stringent 2007 federal diesel emission standards. (The N Series trucks are the same as the Chevrolet and GMC W Series, except for different badges.)

The new diesel model truck offerings come in 12,000- to 19,500-lb gross vehicle weight ratings (GVWR) to accommodate body lengths of 10 to 24 feet and payloads of 6,140 to 13,234 pounds. The gas model line-up has GVWRs from 12,000 to 14,500 pounds for body lengths of 10 to 20 feet and payloads of 7,035 to 9,390 pounds.

The trucks are available in six exterior cab colors: Arc White (standard), Wheatland Yellow, Woodland Green, Cardinal Red, Dark Blue, and Ebony Black II.

In late June, Isuzu hosted a ride and drive event in Santa Barbara, California, to give a select group of editors an opportunity to put the new models through their paces in a variety of driving environments — city, highway, mountain passes, and interstates.


Most noticeable about the trucks is the fresh, rugged, spacious cab design. The fully trimmed interior is bigger in all dimensions — something big and tall drivers appreciate. Also thoughtful is the larger door opening that opens a wide 85 degrees; a lower, wider self-cleaning non-slip entry step; and convenient grab handles.

Other nice standard cab features include tilt and telescopic steering column; power windows and door locks; extra power outlets; improved heating and air conditioning; and plenty of storage areas.

The dashboard is new, with a full complement of easy-to-see gauges and warning lamps. All switches and controls are in easy reach. Space is available for installation of additional equipment, such as CB radios, GPS systems, and rearview cameras.

The cab has enhanced rust and corrosion protection for greater durability, said Dan Cutler, Isuzu Commercial Truck of America's executive director of product development. Design features and increased structural strength make for a quieter ride while providing extra safety for the driver and passengers.

The large windshield and big low-cut side windows increase downward visibility. Sitting behind the wheel, I could see the ground 8½ feet from the front bumper. The large 17-inch-by-8-inch side mirrors with integrated convex sections provide good rear visibility.

Particularly functional elements are roof water channels at the top of the windshield and on the cab roof that direct water away from the center of the windshield for improved visibility in adverse weather. The front panel and chrome grille is easily removed, exposing electrical connections, fresh air filter, wiper motor, and linkage for easy access and maintenance.


Diesel power is supplied by a 5.2-liter overhead cam 4HK1-TC turbocharged, intercooled engine mated to the new Aisin A465 heavy duty six-speed automatic transmission with double overdrive. The engine has been boosted to 205 hp at 2,400 rpm, up from 190 hp, and has more torque, 441 lb-ft at 1,850 rpm, up from 387 lb-ft. “It is the most powerful and highest torque engine in the LCF class,” Cutler said.

The engines use an advanced gas recirculation (EGR) system with a variable geometry turbocharger and a diesel particulate filter to meet the 2007 emission requirements. All exhaust components are neatly packaged between the frame rails. Regeneration (cleaning of the filter) is done automatically as the vehicle is driven throughout the day.

“The engine has a B10 durability rating of 310,000 miles, meaning 90% of the engines should reach this mileage before overhaul, provided good maintenance practices have been followed,” said Cutler.

The NPR and NPR HD truck models are available with the Vortec 6.0-liter V-8 gasoline engine backed to a Hydra-Matic 4L80 four-speed automatic with lockup torque converter and overdrive. This engine delivers 325 hp at 5,000 rpm — 25 more hp than the previous version, and 360 lb-ft of torque at 4,400 rpm.


Overall, the trucks — all had nearly full loads — performed well and were highly maneuverable. An advantage of a LCF truck versus a conventional is the LCF is more agile with the driver sitting over the engine and front axle. Plus, the Isuzus have a 42.5-degree wheel cut, making them even more maneuverable.

Braking on the vehicles, which use hydraulic brake discs on the front axle, self-adjusting drums on the rear, along with four-channel ABS, was impressive. The Electronic Brake Distribution system consistently and automatically adjusts the brake force to all wheels, based on the load on each wheel. This provides more balanced braking with less jarring on the both the driver and cargo. An exhaust brake provides additional stopping assistance.

Other useful features are the standard side turn signal and cornering lamps that provide extra light at night for turning.

New models

Included in the ride and drive was Isuzu's new 2008 Onyx Edition — a fully loaded NPR HD truck with a host of special features, including an air deflector, stainless steel wheels, and special all-black exterior onyx paint with classic silver highlights. The 14,500-lb GVWR truck has a 132-inch wheelbase and a 14-foot Supreme van body.

Also new this year are NQR and NRR Long Wheelbase (LWB) models, available with 200-inch and 212-inch wheelbases, permitting 22- and 24-foot body lengths, respectively. The NRR is a 19,500-lb GVWR truck with a payload allowance of 13,234 pounds. The NQR has a GVWR of 17,950 pounds and an 11,749-lb payload capacity.

The N and W Series have been the number one selling LCF truck in America every year since 1986, Cutler said. About 86% of those Isuzu trucks are still registered today.

Isuzu has begun rolling out its Isuzu Diagnostic Service Support (IDSS) system. It is a comprehensive diagnostic tool that uses a laptop computer and an industry standard J2534 vehicle interface device. The system is kept updated via the Internet.

“IDSS will allow us to collect data on how a vehicle is performing,” said Todd Bloom, a General Motors Isuzu Commercial Truck vice president. “By putting this information in a database, we'll be able to issue a ‘health report’ on a vehicle, comparing it against similar vehicles.”

The intent is to analyze the accumulated data and see how Isuzu trucks are operating. Eventually the goal is to be able to identify potential vehicle trouble before it occurs and to make changes to allow trucks to run longer and more efficiently.

IDSS has expandability for further improvement of transportation and vehicle management, Bloom said, as it is based on the Mimamori vehicle diagnostic system. Currently being used on Isuzu commercial trucks in Japan, it is a full telematics system that provides real-time information on various vehicle operations.

These include fuel consumption, vehicle location, and driving conditions such as gear shifting, acceleration, and braking behavior. This data is collected and analyzed for more efficient ways to operate and manage the vehicle.