If it's true that noise and road vibration contribute to driver fatigue, Freightliner's recently updated Classic and Classic XL models might be just the antidotes for those long, tiring days behind the wheel.

The trucks now sport improved suspensions – including an optional front-axle air ride – and better sound abatement. These changes, announced in January, benefit drivers and provide greater manufacturing efficiencies, with some of the parts borrowed from other vehicles in the company's stable. "[We're using] a chassis platform from the Century-Columbia-Coronado series," says Bruce Barns, Freightliner's director of product marketing. "We tuned the ride, fore and aft...and we have a wider track steering axle for a better turn angle. But that's where a lot of the Classic's performance issues [originated]."

Although used by a number of fleets, the Classic models are clearly aimed at the owner-operator crowd, featuring traditional "large car" styling. The hoods are wide and square and nearly long enough to house a Subaru – the 132-inch BBC XL's hood stretching a full 12 inches beyond that of the standard Classic.

I spent a day touring northern Indiana in a tricked-out Classic XL. In another life, I owned a 1980 FLC-120, the Classic's predecessor, so I felt uniquely qualified to assess the new truck's many refinements.

My test began in the rain at the Bosch Automotive Proving Grounds just outside of South Bend. Freightliner rents space at the facility and employs a small staff. As far as I could tell, these people spend their days building and destroying prototypes – all in the name of research. Gary Holse, a project engineer at the site, has been known to buy competitors' trucks and destroy them, too – also in the name of research, of course.

My test truck was coupled to a dry van filled with cement barricades for a combined estimated gross vehicle weight of 78,500 pounds, typical tonnage for most truckers. I headed east on Indiana 2, then south on U.S. 31, a road that lacked the potholes, breaks and bumps necessary for any serious analysis of a newly improved suspension. This aspect of my test drive wouldn't be fulfilled until later in the day, when I encountered a particularly decrepit stretch of U.S. 6.

Soon, the skies began to clear, and I spied a McDonald's that appeared to accommodate truck parking. This was not the case, however, and I was forced to back out the way I came in. The maneuver made me appreciate the truck's power mirrors and its slightly shorter turning radius. Barns at Freightliner says engineers were able to sharpen the Classic's wheelcut by a couple of degrees – it's nearly 50 now – with a narrower steering gearbox that gives the front tires a little more side-to-side room. I made full use of this enhancement while a handful of fast-food diners patiently waited for the intersection to be cleared.

During the early part of my drive, I hadn't paid much attention to the truck's engine, even though it clearly delivered considerable oomph Ð along with a pronounced turbo whistle that reminded me of an old Cummins 335 that I had in the '70s. The engine, a 500 horsepower Caterpillar C-15 "bridge," fed its power to an Eaton Fuller RTLO-18913A (13 speed) transmission and Meritor drive axles, geared at 3.42:1. This powertrain would be well suited for states like Nebraska and Nevada, where the speed limit is 75 mph, but it was overkill for Indiana's 55 mph limit on U.S. 31. I repeatedly found the speedometer needle inching to the backside of 70 mph. I eventually wised up and set the cruise control for a more acceptable pace.

The truck's most obvious upgrade is the optional air ride front axle, a component that's been available on other Freightliner trucks for more than a year. The use of a common chassis enabled its installation on the Classic. Unlike most drive- and trailer-axle air suspensions, this component is lighter than a spring alternative, trimming roughly 50 pounds of vehicle weight. It's also relatively inexpensive: about $300, according to the data book. The setup, built by Hendrickson, originally carried its manufacturer's product name, AirTek. But now it is called AirLiner, to match Freightliner's other air suspensions.

A fully air-sprung chassis absorbs a lot of road-surface violence, but it's not solely responsible for a supremely smooth ride. To further isolate drivers from jolts and vibration, trucks need a compliant cab suspension. The new Classic models have that, thanks to a few simple design changes. First, engineers repositioned the cab's air springs and shocks farther outboard to boost stability. Then they used larger diameter fittings and lines to increase the springs' airflow, quickening their response to movements. The result, at least in the XL I was piloting, is a luxuriously fluid motion without excessive leaning and pitching. It's about as much comfort as a Class 8 truck can offer.

The newly improved Classic and Classic XL should do well for Freightliner, once owner-operators return to the market. The trucks' boldly traditional styling has been matched with a superb ride, slightly better maneuverability, a stronger – yet lighter – frame and a bit less interior noise (at least during launches). Now that the important stuff has been done, maybe the company's engineers can make the windshield wipers wider and the cup holders deeper. When that's accomplished, I'll gladly re-up for another trip through a Hoosier rainstorm, Big Gulp in hand.

Just the Facts

• Engine: Caterpillar C15, rated at 500 hp and 1,850 lbs.-ft of torque
• Transmission: Eaton Fuller RTLO-18913A
• Clutch: Eaton Fuller 15.5" ceramic two-plate Easy Pedal
• Drivelines: Meritor 18N (main); Meritor 17N (interaxle)
• Front Axle: Hendrickson SteerTek, rated at 12,000 lbs.
• Rear Axles: Meritor RT-40-145P R series, rated at 40,000 lbs., 3.42 gear ratio
• Suspension: AirLiner (front and rear)
• Brakes: Meritor 15X4 Q Plus (front), Meritor 15.5X7 Q Plus (rear)
• Tires: Michelin XZE 275/80R22.5 (front) Michelin XZA 275 80R22.5 (rear)
• Fuel Capacity: Dual 150 gallon tanks