A Once Over

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 trucks are offered in 12,000- to 19,500-pound 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.

Isuzu recently conducted a ride and drive program to help introduce the new trucks. Included in the program 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. A 14,500-pound GVWR truck, it has a 132-inch wheelbase and 14-foot Supreme van body.

Also new this year is 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-pound GVWR truck with a payload allowance of 13,234 pounds. The NQR has a GVWR of 17,950 pounds and an 11,749-pound payload capacity.

Frame

The 33.5-inch wide industry standard frame has been improved and strengthened with a 44,000 psi rating. It is smooth and flat to make body and equipment installation easier.

Exhaust components have been moved inward to keep outside of frame clean.

In addition, the frame has new 80/40mm modular hole spacing that gives more flexibility for optional equipment or body mounting/swapping.

The fuel tank is positioned within the frame rails at the truck's rear, with through-the-frame fuel fill for lower body height and a longer fuel filler hose to accommodate 102-inch bodies.

Weather pack body builder connectors are located at the end of the frame and behind the cab on the driver's side for improved body mounting and less electrical problems. The turn signal flasher is now set up for LED lamps for reduced body mounting cost.

There is a 6,830-pound capacity front I-beam axle to handle heavy loads and to maintain correct alignment for reduced tire wear. It has a 8,440-pound taper front suspension with shocks and stabilizer bar for improved ride and handling.

At the other end is a 14,550-pound capacity full floating rear axle. A multi-leaf two-stage rear suspension with rear shock absorbers help make for an improved ride when the vehicle is empty and better stability when loaded.

Engines

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, “making it the most powerful and highest torque engine in the LCF class,” said Dan Cutler, Isuzu Commercial Truck of America's executive director of product development.

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. 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 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.

The trucks' rear engine cover has an improved appearance and engine component protection.

Brakes

The 2008s have hydraulic brakes — discs on the front axle, self-adjusting drums on the rear, along with four-channel ABS.

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.

There is an exhaust brake for additional stopping assistance.

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, an Isuzu Commercial Truck of America vice president. “By putting this information in a database, we'll be able to issue a ‘health report’ on a vehicle, comparing it against other similar vehicles.”

The intent is to analyze the accumulated data and see how Isuzu trucks are operating. The goal is to be able to identify 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.

Cabs

Most noticeable about the new trucks is the spacious cab design. The interior is bigger in all dimensions, and has larger door openings; doors that open a wide 85 degrees; a lower, wider self-cleaning non-slip entry step; convenient grab handles; and plenty of driver comfort and productivity features.

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

The cab has enhanced rust and corrosion protection for greater durability, said Cutler. Design features and increased structural strength make for a quieter ride while providing extra safety for the driver and passengers.

The large windshield and large low-cut side windows increase downward visibility. The large side mirrors with integrated convex mirrors provide good rear visibility.

Roof water channels at the top of the windshield and on the cab roof 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.

About the Author

David Kolman