Isuzu Commercial Truck of America Inc introduced its all-new N-Series at the National Truck Equipment Association annual New Model Truck Product Conference in Dearborn, Michigan. It delivers more cab room, enhanced safety features, and more power, along with meeting the new, more stringent 2007 US and California diesel-emissions standards.
The wheelbase stretches to 200" on NQR and 212" on NRR models - increases of 24" and 36", respectively, from the previously longest available wheelbase of 176". The longer wheelbase is available on NQR 22' models and NRR 22' and 24' models.
Isuzu has launched a special body program through Supreme Corporation to provide special pricing for 22' and 24' dry-freight vans.
For 2008, the overhead cam 5.2L 4HK1-TC diesel engine delivers more power and reduced emissions. Horsepower increases to 205 at 2400 rpm (up from 190) and torque increases to 441 lb-ft at 1850 (up from 387). It covers GVW ranges from 12,000 lb to 19,500 lb. With its B10 durability rating of 310,000 miles, 90% of the engines should reach this mileage before a major component failure, provided good maintenance practices have been followed, according to Dan Cutler, executive director of product development LCF.
The 5.2L diesel engine is equipped with a standard fuel/water separator that is heated with returned fuel and features a dash-mounted warning lamp. This separator warns the driver when water is present in the fuel filter and needs to be drained, which helps prevent vehicle down time and supports a more efficient operation. The 5.2L diesel can be mated to the new Aisin A465 heavy-duty six-speed automatic with double overdrive, or with a six-speed manual transmission with all forward gears synchronized.
The 5.2L diesel engine meets the emissions requirements that went into effect on January 1 — all diesel engine manufacturers must reduce nitrogen oxide (NOx) and particulate matter (PM) emissions by 90% compared to the previous diesel engine standards, which were established in 2004.
To reduce nitrogen oxide levels, the 5.2L diesel engine uses an advanced exhaust gas recirculation (EGR) system and a variable geometry turbocharger.
To reduce particulate matter, a ceramic honeycomb channel diesel particulate filter (DPF) was created to capture sulfate particles and soot. Exhaust gases are directed through the channels and a porous material that traps the particulates. To clear the particulates and prevent clogging, a regeneration process occurs to burn off the trapped particulates and clean the filter using high exhaust gas temperatures.
Regeneration in Isuzu trucks can occur through self-regeneration, an automatic process that occurs as the vehicle is driven throughout the day and does not require driver involvement. The vast majority of vehicles will regenerate automatically. Forced computer-initiated regeneration occurs if the vehicle operation does not produce exhaust gases hot enough for the automatic process to occur.
In the event that the computer cannot force regeneration, a control light will alert the driver to activate a dashboard switch to initiate the regeneration process. Special system-sensing and control software was developed to precisely control engine combustion and DPF regeneration.
To meet the EPA regulation for lower diesel fuel sulfur emissions, Isuzu-designed emissions systems work efficiently with the new fuels and lubricants. The ‘07 emissions regulations also require all crankcase gas emissions to be reduced. To comply, a closed crankcase system was added to reroute ventilation gases back into the engine for combustion.
Helping to reduce operating costs while increasing vehicle uptime is a new 10,000-mile oil and oil filter interval on N-Series models equipped with the 5.2L diesel engine.
For Isuzu N-Series customers who prefer a gasoline engine, NPR and NPR HD models are available with the Vortec 6.0L V-8 engine. For 2008, the Vortec 6.0L delivers 325 horsepower - 25 more than the previous version - and 360 lb-ft of torque. These models are mated to the Hydra-Matic 4L80 four-speed automatic with lockup torque converter and overdrive.
The Vortec 6.0L is 50-state compliant with federal CFFV/LEV and California ULEV emissions requirements. It has a 200,000-mile design life and is backed by a three-year/36,000-mile warranty. Customers may purchase extended service plans that cover their vehicles for up to five years/100,000 miles.