Navistar Chassis Update at NTEA

NAVISTAR International Transportation Corporation, held an informal seminar to update NTEA members. Navistar managers who spoke during the seminar included Rex Kuhn, special equipment consultant; Al Ambrosini, southeast regional sales manager in the engine division; and Bill Cheever, northeast regional sales manager in the engine division. They presented general information on Navistar and specific information about International truck chassis.

Navistar recently broke ground for a 50,000-sq-ft expansion at its technical center in Fort Wayne, Indiana, Kuhn said. The company will hire about 400 designers and engineers over the next 12 months to work on Navistar's Next Generation Vehicle (NGV). Production will begin on the NGV in 2001, Kuhn said. In the exhibit hall, another new Navistar truck, the 4700 LTX chassis, was on display.

New Product Information Some of the product information presented by the Navistar managers includes the following:

Beginning with November or December production, Navistar hopes to use Allison automatic transmissions in its 4x4 and 6x4 4000 series medium-duty trucks.

Navistar's Diamond Spec ordering procedure for heavy-duty trucks allows customers to tailor a truck for a specific application or vocation. Customers can make specifications ranging from powertrain components and cabs to wheels and tires from 11 or 12 modules. Customers using Diamond Spec will receive a guaranteed production date and increased warranties.

A new six- or 10-switch panel is now in production. The new switch panel replaces a cupholder in the instrument panel. The molded-plastic panel has a better appearance than previous switch panels.

Another new item on 4000 Series Navistar trucks are International Diamond Life pin-slide hydraulic brakes, which can be used on trucks with up to a 33,000-lb GVW. Two major benefits are easy service and installation. A technician can easily access and service the brake pads by removing one pin.

Navistar's new single-box engine controller is located on the upper left-hand side of the I-6 DT466 or 530 engines. The single-box controller replaces the three-box system used by Navistar since 1994. The three-box system used a 286 microprocessor. The new single-box controller has a twin-Pentium microprocessors, which control more vehicle functions and provide better emission control.

This is important because on January 1, 1998, an emission regulation decreased allowable NOX emissions 20% from five grams to four grams per horsepower per hour. Another change in 2004 requires a 62% reduction from four grams to 2 1/2 grams of NOX per horsepower per hour.

Electronic Control Features Once electronics are installed on an engine to control emissions and performance, a lot of other functions also can be controlled, Ambrosini said. Some electronic engine control features currently available on production models are:

The cruise control has dashboard switches that turn the cruise on or off and activate the coast, resume and accelerate functions. The cruise controls are similar to automobile controls.

A road-speed governor limits the vehicle's maximum speed. This feature can be ordered from the factory. If it is not ordered, the factory will automatically set a default speed of 62 mph.

An engine warning and shutdown system monitors coolant temperature, coolant level, oil pressure, and engine overspeed. This system will either illuminate a dashboard light or shut down the engine after a 30-second warning.

Co-ambient protection automatically increases engine idle speed if the temperature is below a preset point and continues a faster idle until the engine temperature reaches 160 degrees F.

An idle shutdown timer turns off an engine that idles in unattended operation for a preset time ranging from two to 120 minutes. The factory default setting is five minutes for the idle shutdown timer.

The engine has a tattle-tale function that sets fault codes when an automatic function is disturbed, Ambrosini said. If an electronic engine is restarted after an automatic shutdown, the tattle-tale function sets a three-digit fault code in the powertrain control module that says the idle-shutdown timer was overridden.

A change-oil-and-filter light is now standard on Navistar trucks and chassis.

Miles, hours, or gallons of fuel can be preset by the customer or Navistar. When the vehicle reaches one of these preset values, the change-oil-and-filter light will illuminate.

Electronic pedals provide acceleration by wire with no mechanical linkages that can jam or need adjustment. A control built into the accelerator pedal tells the electronic control module (ECM) how much fuel to deliver to the engine.

Electronic fan-drive and shutter controls are programmable.

An electronic engine-retarder, exhaust-brake control is now available.

Diagnostic trouble-shooting lights flash in the instrument panel to identify fault codes. Lights flash and pause in sequence to provide three-digit fault codes.

"If you can set the clock on your VCR at home, you can diagnose a problem on one of our electronic engines," Ambrosini said.

Monitoring Fault Codes Navistar electronic engines have 157 different fault codes and provide the most probable solution for each code. The flashing fault-code feature is on every truck and bus built by Navistar.

Each fuel injector is easily monitored on an electronic engine for proper operation. If not operating properly, a fault code can be set for each malfunctioning injector.

Event logging monitors high coolant temperature, low coolant level, low oil pressure, and engine overspeed. The last two times an event occurs, it is logged within three minutes or 1/10 of a mile. The owner has an indication of where and when the event happened.

Other electronic control options are already available from the factory, Cheever said. Customers can modify factory settings with electronic service tools such as the MPSI Pro Link 9000 hand-held electronic service tool.

"We see a lot of vehicles delivered from body companies to the end users with fault codes still inside the PCMs," Cheever said.

Cheever added that he was encouraged by the number of body company representatives at the seminar who use the Pro Link 9000 service tools. It is important to identify and clear fault codes before delivering a vehicle to a customer.

Each engine manufacturer produces a data card that works with a multi-protocol cartridge (MPC) that slides into the back of the Pro Link tool. The MPC and engine data card will update any Pro Link tool.

Never Splice Harness With a single-box controller, body builders can access electronic-control circuits without splicing into the wiring harness, Ambrosini said. The wiring harness on an electronic engine should never be spliced.

"The harness wires conduct very precise voltages to operate different pieces of equipment," Ambrosini said.

On an in-line six-cylinder engine, sixteen wires are located in a box behind the wiring harness where body builders can modify engine speed controls, Ambrosini said. A remote PTO-control provision is located within the wiring harness.

Some of the wires are feeds for a remote tachometer, speedometer, and warning and shutdown lights. Another wire is for a hydraulic pressure governor to monitor water pressure output on firetrucks after the engine speed is set. When additional hoses are opened up, the engine speed will increase to maintain water pressure.

For the different functions, the wiring harness has tags and each wire is numbered and color-coded. The wires are capped with plastic shrink-wrap. Navistar has several connectors that should be used for junction box connections. The connectors are available from Navistar and its dealers.

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