Not long ago, truck buyers looking for comfort as well as towing capability above the F-350 or any competitive 3500 pickup had to purchase Ford's commercial medium-duty F-450 or F-550 chassis cab. An aftermarket outfitter would then install a custom cargo bed, restitch the interior with leather seating and add other amenities favored by RV enthusiasts, racecar haulers or ranchers pulling a 10-stall horse trailer.

Ford added those responsibilities to the factory assembly line a few years ago, and the result continues with the consumer-friendly 2012 Ford F-450. Just like other F-Series models, the 450 is available in a wide range of trim levels, including the cowboy-chic King Ranch edition. The downside is that only one configuration is offered: crew cab with a long bed, diesel engine and four-wheel drive.

Endowed with big-rig styling and plus-size dimensions, the F-450 can tow up to 24,500 pounds with a fifth-wheel hitch. Pulling power is generated by a 6.7-liter V8 turbodiesel. It's mated to a six-speed automatic transmission that draws favorable comparisons to GM's venerable Allison automatic for its tow/haul shift strategy on mountain roads, which is especially helpful for controlling downhill speeds.

Judging solely by the numbers, the Ford F-450 Super Duty is in a class by itself as the only 4500 model available in full cargo-bed dress for the consumer market. Competitive 3500 models (including the Ford F-350) max out with around 22,000 pounds of towing capacity for crew cab models. If your trailer weighs another 2,500 pounds, you have only one choice. It will be a big hit in the pocketbook, as the base XL model starts at just under $50,000 while a fully loaded F-450 King Ranch easily clears $70,000.

The 2012 Ford F-450 Super Duty is offered in just one configuration: a crew cab mated to an 8-foot cargo bed, with four-wheel-drive and dual rear wheels (DRW or dually). Customers, however, do get a choice among the four familiar trim levels also found on the F-250 and F350 models: XL, XLT, Lariat and King Ranch.

Standard on the base XL are 17-inch forged aluminum wheels, a black grille and bumpers, running boards, roof clearance lights, manual-telescoping trailer-tow mirrors, air-conditioning, vinyl upholstery and floor coverings, a 40/20/40-split front bench, a 60/40 split-folding rear bench seat, a tilt-and-telescoping steering wheel and a two-speaker AM/FM radio.

Stepping up to the XLT adds a chrome grille and bumpers, heated outside mirrors, cruise control, full power accessories, keyless entry, an integrated trailer-brake controller, carpeted floor, cloth upholstery, lockable second-row underseat storage with a power point, and a four-speaker sound system with CD/MP3 player and auxiliary audio jack.

The Lariat trim level features foglights, power-telescoping mirrors, rear parking sensors, a power rear sliding window with defrost, chrome tubular step bars, dual-zone automatic climate control and leather interior upholstery. Additional standard equipment on the Lariat include a 4.2-inch LCD multifunction screen, wood-grain trim, an auto-dimming rearview mirror, power-adjustable pedals, the Ford Sync voice activation system and an eight-speaker audio system with satellite radio. The front seat also features a center console and 10-way power seats for the driver and passenger.

The range-topping King Ranch piles on power-folding and telescoping tow mirrors, two-tone paint, a body-colored grille with chrome insert, lighted running boards, unique exterior and interior badging, remote start, upgraded Chaparral leather upholstery, heated and ventilated seats, driver seat memory and a rearview camera.

Some features on the Lariat and King Ranch trims are available on the XL and XLT models. Other add-ons (depending on trim level) include a stowable bed extender, a transmission power take-off (for powering accessories like snow plows), fifth-wheel mounting points (compatible with Reese hitch units), a spray-in bedliner, a sunroof, integrated accessory switches and a hard-drive-based navigation system.

The available Ford Work Solutions package is offered on XL and XLT models and adds an in-dash computer that is customizable to suit commercial users and fleets. Other work-related options include snow plow and camper prep packages and the FX4 Off-Road package that provides skid plates and Rancho-brand shock absorbers.

A turbocharged 6.7-liter V8 diesel is the only engine available in the F-450 pickup. It packs a healthy 400 horsepower with 800 pound-feet of peak torque. To meet the latest emissions standards, the diesel engine uses an after-treatment system that requires replenishment of diesel exhaust fluid (DEF) about every 7,500 miles. The F-450 also features engine exhaust braking to help maintain control on downhill grades while towing.

A six-speed automatic and four-wheel drive are standard, as is a limited-slip rear axle. Properly equipped, the F-450 Super Duty can tow up to 17,500 pounds with a conventional trailer setup, some 1,500 pounds more than the 2011 model. When configured for fifth-wheel towing, this figure increases 100 pounds from the previous year to a class-leading 24,500 pounds. Maximum payload capacity is also up, jumping 340 pounds to 5,260 pounds.

The 2012 Ford F-450 Super Duty comes standard with antilock brakes, trailer sway control, hill start assist, front seat-mounted side airbags, side curtain airbags and an SOS post-crash alert system. Ford's AdvanceTrac with Roll Stability Control isn't available on DRW models and traction control is handled strictly through throttle management; there is no interaction with the brake system.

An integrated trailer brake controller is standard on XLT and higher models, while the Lariat trim level adds rear parking sensors and power-adjustable pedals. A rearview camera is optional on the XLT and Lariat and standard on the King Ranch model.

There is no direct competition for the 2012 Ford F-450, but the overall line of Ford Super Duty trucks is noted for a pleasant ride quality and relatively restrained noise from the engine, road and wind. The Ford F-450 is nearly 22 feet long and 9 feet wide at the mirrors, so it can be awkward in tight traffic and crowded parking lots. The front track on the F-450 is 6 inches wider than its F-250 and F-350 brethren, so turning around also requires more room. Another downside is the steering, which feels numb and instills less confidence (especially when towing) than other heavy-duty trucks.

Of course, towing is a big part of the Super Duty's capabilities, and the 6.7-liter V8 turbodiesel is up to the task. Even when lugging a 10,000-pound trailer up a steep grade, the diesel climbs with ease and the six-speed transmission is never caught hunting between gears. Drivers may also selectively lock out higher gears to ensure optimal towing prowess, going uphill or down, and descents are also more secure due to the diesel's exhaust brake.

The 2012 Ford F-450 Super Duty has an industrial-themed interior and it looks a little dated compared to heavy-duty trucks from GM and Ram, especially in the lower trim levels where hard plastics prevail. Opting for the Lariat will provide a decidedly upscale experience, with rich leather and added amenities, and the King Ranch model is arguably the best-executed theme truck on the market.

Storage and utility options for the Ford F-450 include lockable bins under the front and rear seats. The rear bin can accommodate long items like a hunting rifle and provides a 12-volt power point to charge computers or cell phones. The available front seat console can be configured to accommodate a laptop, hanging files and other mobile-office supplies. It also includes a 110-volt household-style outlet. The 4.2-inch LCD multifunction display standard on Lariat and King Ranch models allows the driver to customize settings and relays trip computer, fuel economy, towing and off-road information.