How Specifications Afffect International HV Performance

Key takeaways

How International HV trucks can be specified.
International HV features.
Driving evaluation of the International HV.

It’s a cloudy, chilly day in northern Indiana and I’m at International Motors’ proving grounds, driving a dump truck over a section of test pavement, grasping the steering wheel and saying thank you to my air-ride seat as the vehicle reacts almost violently to the intentionally rough road surface. I’m peripherally eyeballing the guy in the shotgun seat actively bounce up and down because his seat is bolted solidly to the steel floor.

He’s Paul Cooper, a vocational segment manager for International, who’s guiding me through the off-road course. He grins cheerfully and, being loyal to his employer, does not complain except indirectly, observing that the previous run over this stretch in another HV went more smoothly.

We were in an HV509, outfitted for snow plowing and utility duty as the Missouri Department of Transportation would spec it, including bright yellow paint. It’s a seemingly simple 10-wheel truck with a no-frills interior, including slick vinyl seat covers.

HV mixer’s interior shows highly legible gauges and easy-to-reach switches and controls. Wide single-piece windshield and sloping hood offer a good view ahead.

The earlier ride was in an HV615 set up as an image-conscious dump-trucking fleet or owner-operator might, with air-ride seats for the passenger as well as the driver, plus other upscale interior appointments, and chrome and polished-metal exterior trim. Chassis equipment included two liftable axles ahead of its tandem, a “quad” setup as used in Wisconsin and other states where weight laws favor it.

This outing was arranged by Nick Smith, International’s press relations manager, as a follow-up to the announcement of the updated HV series late last summer. Past versions of this series were collectively called Work Star, during a period when International used descriptive names for its products. The current foreshortened abbreviations are also meaningful with some interpretation: HV, for Heavy Vocational, is the builder’s main Class 8 work-truck line utilizing a steel cab that’s also used in other heavies and medium-duty models.

Work for me this day started with a briefing by Cooper and Smith on International’s ambitions and the HV changes. The builder has long been successful in municipal bidding and other vocational sales, and it’s trying to extend that success to other markets.

Regarding vocational-truck engines, Cooper said International uses its own S13 diesel and Cummins’ B6.7 and L9. The S13, developed with Scania of Sweden, emphasizes simplicity: Its turbocharger uses fixed vanes instead of variable-geometry vanes; the amount of exhaust gas recirculated into the cylinders is reduced and there’s no EGR cooler. Also eliminated is the “seventh” fuel injector ahead of the particulate filter to induce heat, and no fuel-fired “active regens” are needed. Instead, high-efficiency fuel combustion in the cylinders and increased urea dosing helps purify the exhaust.

The bright-blue quad had an S13 Integrated powertrain with a 475-horsepower version of the 12.7-liter diesel and an Eaton-made, International-branded T14 automated manual transmission. The self-shifting tranny had two crawler ratios and 12 driving ratios, and it worked well with the engine, whether on- or off pavement.

Optional LED under-hood work lamp can aid inspections and repairs in dim light and darkness.

Likewise for the 360-horsepower 8.9-liter L9, mated to an Allison 3000 RDS automatic, in the MoDOT truck. Automated gearboxes have become popular among buyers of freight-hauling highway tractors but not with users of on/off-road vocational trucks, who still favor the torque-converter-equipped Allisons for their smoothness and proven reliability.

As for the updated HV series, many changes are under their skins. For instance, 270 pounds were slashed from the main front crossmember, and the Diamond Logic electrical system has more sensors, including some that automate checking of fluid levels, and additional 130-amp remote power modules to simplify body mounting and wiring. Outside trim has also changed.

Starkly obvious on the MoDOT truck was the nose’s flat-black grille, which looks like someone forgot something, especially when parked alongside the fancier quad with its cheerful chrome-trimmed grille.

To either side of the grilles in both trucks were cool-burning LED headlamps, with heating grids to melt snow and ice; these are optional while halogen lamps are standard. Black bezels surrounded the lights on the MoDOT truck but those on the quad were chromed. Composite hoods now have separate fenders that can easily be replaced if they get bashed in action. The hood tilts easily thanks to a special support mechanism.

Standard two-tread stair arrangement makes for a ‘one, two, three and in’ exercise while climbing and entering the HV615’s cab. Short-legged drivers might appreciate an optional third additional tread that can be placed between the existing pair to ease an ascent.

Steps leading to the cab have the familiar two treads, but a newly available third step, vertically adjustable to suit a driver, can ease the climb up. That’s the beauty of the spec’ing process: You can set up a truck for your drivers and your hauling jobs, and the results will include the performance, workability, ride quality, and driving character you want. These two test trucks were prime examples.

The MoDOT snow-plow truck had a bare-bones, “your tax dollars at work” appearance. Yet it was anything but simple, and its Order Content list was as long as the quad’s. Government trucks tend to favor tried-and-true components, and that was the case with this one. It had S-cam drum brakes on all axles, all from Meritor, with Bendix anti-lock braking systems and Haldex slack adjusters.

Among specialty equipment were high-set plow lights perched on the fender-mounted mirror brackets. And there was an integral forward frame extension to accommodate the plow mount; Cooper noted that the extension’s rails are part of the main frame rather than bolted-on separate pieces, yielding a cleaner appearance and reduced mass from fasteners and overlapping steel.

What’s in a name?

Entrance signs at the proving grounds still say “Navistar,” the company’s former name, as its European owners, Volkswagen AG’s Traton Group, decided to drop the snappy mid-1980s moniker and go back to International, with Motors LLC as a suffix.

That harkens back to the old International Harvester that originated in the early 20th century, or 19th century if one counts Cyrus McCormick and his revolutionary mechanical reaper, to which the company traces its beginning.

The blue quad looked dipped in chrome, but it was every bit as serious and its payload was several tons greater, thanks to its two pusher-type auxiliary axles. International will now mount up to three lift axles at the factory, something that in former years was left to upfitters.

Both trucks were fitted with 20,000-pound steer axles. On the quad, 20,000-pound parabolic leaf springs helped carry the powertrain and payload. The MoDOT truck needed the capacity to support the heavy plow mount and blade, but used slightly softer 18,000-pound leafs. Both trucks had Meritor rear tandem axles riding on Hendrickson HMX-EX400 walking beam suspensions, but the quad’s longer wheelbase—242 inches vs. the MoDOT’s 177 inches—helped smooth the ride somewhat.

Each truck carried a load of sand in its dump bed for a gross weight of about 45,000 pounds, Cooper said. That was enough to settle the suspensions and provide a modest load to the two diesels. The result was good acceleration and reassuring stability at highway speeds.

HV615 cruises easily along the proving grounds’ long oval test track. Chassis equipment includes two “pusher” lift axles, not needed here because of a moderate load in the dump bed and GVW of 45,000 pounds. Chrome and bright-metal trim adorns this upscale version of the HV series which offers considerable flexibility in specifications.

On the long oval test track, I had both trucks up to 60 and 65 mph and noted the tach needles pointing at 1,600 to 1,800 rpm, with the quad’s faster 3.58 axle ratio and additional transmission gears allowing easier cruising vs. the MoDOT’s 5.29 ratio and shorter-geared Allison. Off road, whether on gravel or punishing test pavement, both trucks ran well, even with the MoDOT’s bouncing on that rough test stretch.