2008 Ford F-450 Lariat SD 4x4

The all-new '08 Ford F-450 Lariat Super Duty with the 6.4-liter Power Stroke is more tool than toy, making it an irresistible choice for anyone looking for the ultimate tow vehicle.

At 21.9 feet (262.4 inches) from bumper to bumper and 7.9 feet wide (95.5 inches), the F-450 SD Lariat 4x4 is a sizeable truck - more at home on a ranch than in the heart of the city.

The F-450 SD is a timely release now that the RV industry is seeing increased sales of bigger trailers with heavy granite kitchen countertops and large slide-out living spaces.

Unlike the F-350, in which you have more body options, the '08 F-450 is only available as an 8-foot bed with a 172-inch wheelbase and crew-cab design.

With a list of practical features for added power and performance, the '08 F-450 is poised to dominate other tow vehicles in the RV trailer market as toy haulers become more elaborately outfitted.

Inside its leather-clad cabin, this 4-ton truck is as spacious, rugged, luxurious, and ergonomically built as any high-end automobile we've tested. The F-450's combination of large physical size and sophisticated electronics makes for a driving experience that can be an entertaining, educational, and frustrating all at once.

The new '08 Ford F-450 was built in house with final assembly at Ford's Kentucky Truck Plant. Ford uses a new wider and stronger monobeam framerail with riveted and welded crossmembers.

With a gross combined vehicle weight (GCVW) of 33,000 pounds, the F-450 Lariat automatic (4.88 limited-slip rear axle ratio) has an incredible 24,000-pound tow capacity and 6,000-pound payload capacity. Add to that an impressive 16,000-pound tow rating on a conventional hitch, and you'll quickly see the benefits of owning such a powerful truck.

As mentioned, the release of Ford's stout F-450 SD is timely now that the RV industry is seeing increasing sales of its bigger trailers with heavy granite kitchen countertops and large slide-out living spaces on the rise.

Owning an F-450 is a big commitment: At $56,255 dollars, it isn't cheap. If you tow frequently and tend to keep your vehicles for several years, investing in an F-450 might pay off in the long run. Unfortunately, all heavy-duty pickups seem to be pricing themselves out of the market.

Round One: Road Test

The '08 F-450 Lariat SD automatic is a stylish work truck with a 24,000-pound tow capacity.

We mapped out a route through California, Arizona, Nevada, and Utah in varying temperatures and terrains. From low-slung motel entrances to tiny convenience store parking lots and off-road campsites, we put the new F-450 4x4 in as many real-world situations as possible during our initial drive. It's tall and takes up most of a highway lane from wheel to wheel, so you have to learn the exterior parameters and turning radius of the F-450 with and without a trailer in tow.

Leaving California, we hitched up a dual-axle trailer loaded down with several Yamaha ATVs to the 8,687-pound truck for 1,200 miles. Total trailer weight was about 7,500 pounds - well below the trailer tongue-load weight threshold of the F-450. This gave us a sense of what it could do but by no means pushed it to its limit.

Keeping a mostly constant speed between 65 and 70 mph, the truck averaged 7.5 to 9.5 mpg with the trailer at the bumper. The variance in fuel mileage was probably due to a combination of traffic, wind, and hills. More importantly, the truck steadily maintained speed and performance without so much as an engine stumble or erratic transmission gear change.

Power for the 6.4-liter diesel is assisted by twin sequential turbochargers with 42 pounds of boost.

We weren't gentle on the F-450 as we powered up steep mountain grades with the outside temperature nearing 100 degrees F. We did this in cruise control and still clocked a steady speed of 65 mph. With the much improved A/C system keeping the cab a cool 68 degrees, the F-450 didn't lack for power. We could hardy tell the trailer was behind us.

With improved features like large engine cooling fans, a 33-percent-larger radiator, and a water pump that doubles the flow rate from 75 to 140 gallons per minute, engine temperatures remained normal.

Because you won't always be towing a trailer, we unhitched the load and continued our drive with three passengers and a sizeable amount of gear taking up all the bed and most of the fold-down rear seating.