Test Drive: Mack Pinnacle

| August 07, 2007

“Ninety-eight percent of the population will fit into and operate this truck,” Warmkessel says.

The dash of my test truck featured Mack’s driver information display screen, 14 gauges, and dozens of switches and controls, all readable at a glance and/or easy to reach and operate. The cup holders were sturdy and deep enough to work through potholes, swerves and hard brakes.

I didn’t have Mack’s optional CoPilot, an electronic driver tool with a large, easy-to-read screen, but we did have Mack’s optional Grand Touring Cobalt Blue cloth and Ultraleather trim package and the auxiliary power system, designed by Overdrive magazine’s 2005 Trucker of the Year Robert Jordan. The system has two units, both under the bunk: a Webasto heater, which uses a half gallon of diesel during a 10-hour break, and a 10,000-BTU air conditioner run by rechargeable, deep-cell batteries guaranteed for 10 years.

But there is plenty more room under the bunk. There also are various cabinets and shelves and a cavernous over-cab attic that easily doubles the Pinnacle’s storage space.

Other available options include wireless tire-pressure monitoring, door mounted cameras to eliminate blind spots, and a global positioning system that provides maps with information on road conditions, bridge heights and points of interest.

Mack’s Road Stability system, which prevents rollovers and jackknifing, is standard.

“We’re the first original manufacturer in the world to have this standard,” Warmkessel says.

After I familiarized myself with the controls, I headed north on I-15 at the 54 entrance ramp, which put us right on a 2-mile, 2.5 percent upslope. After turning onto the ramp at about 15 miles an hour, I mashed the throttle and held it down. The MP8 got us to 64 miles an hour and made it to 10th gear before the slope’s summit: not bad at all for 415 horsepower.

The speed limit on I-15 in Nevada is 75 miles an hour, so after a few miles at 65 mph to get a feel for the Pinnacle, I got us up to speed.

I was surprised by the performance of the 415-horsepower MP8. The Pinnacle was storming the considerable hills north of Las Vegas on I-15, and the MP8 was still new – far from broken in, when it will deliver its peak horsepower. During the entire 200-mile test-drive, the hills caused the Eaton transmission to drop below ninth just twice: once for a particularly steep climb, and once when we got trapped behind a triple-trailer rig slowed to about 15 mph on a long, steep hill. The only other things to slow the Pinnacle were its air brakes and Mack’s PowerLeash engine brake, which also worked exceptionally well.

On one occasion I topped a hill in the left lane, got quickly back up to 75 mph and rounded a medium-hard right curve – right onto a 5-6 percent mile-long downslope. The Pinnacle’s inertia from the right curve, along with the left lane’s slight incline toward the shoulder, bore down on the Pinnacle, pushing it toward the left shoulder. Gravity took hold of the truck, too, and we shot down the hill.

No problem: I tapped the brake to disengage the cruise control and engage the PowerLeash. From inside the insulated cab, I couldn’t hear the PowerLeash at work unless I consciously listened for it, but it was powerful enough to break the 35-ton rig’s momentum.

The Pinnacle straightened up and slowed down, and within five seconds we were tucked neatly into the right-hand lane. I feathered the throttle on the way down so the PowerLeash wouldn’t slow us down too much.

Comments are closed.

OverdriveOnline.com strives to maintain an open forum for reader opinions. Click here to read our comment policy.