Test Drive: 2015 Ford Pickups Flex Super Duty Towing Muscle

Larger turbo boosts 6.7-liter Power Stroke diesel's torque to 860 lb.-ft., gross combined weight rating to 40,000 lb.

The F-450 has a GCWR of 40,000 lbs., half that of a Class 8 truck.
The F-450 has a GCWR of 40,000 lbs., half that of a Class 8 truck.

Can a pickup haul half the payload of a semi-truck on a 7% grade? It can if it is the 2015 Ford F-450. This truck boasts a 40,000-lb. gross combined weight rating (GCWR) and a maximum fifth-wheel/gooseneck towing capacity of 31,200 lbs. We gained first-hand knowledge of its true capabilities in the mountains outside Charleston, WV. Thanks to a new, larger turbocharger sitting between the 6.7-liter Power Stroke diesel’s V8 cylinders, the engine not only pumps out an impressive 860 lb.-ft. of torque and 440 hp, but it also provides increased engine braking to instill confidence on steep downhill grades.

Manually controlled by pushing a button on the dashboard close to the driver’s right knee, the engine brake helps reduce wear and tear on wheel brakes. On our test drive it controlled 36,000 lb. GCW rolling down a five-mile-long, 7% grade with only periodic dabs at the service brakes. At the bottom of this same hill, we saw smoke billowing from the wheels of several Class 8 trucks. During repeated trips up and down the hill, the F-450’s combination of Tow/Haul feature and engine braking proved up to the task.

With the truck loaded to a GCW of 34,000 lb., it would pull a consistent 55 mph up the interstate’s 7% grade. Loaded to 36,000 lb., the truck still managed to pull that grade at 45 mph.

All of the diesel-powered Super Duty trucks offer increased capability due to the improved 6.7-liter Power Stroke. We also tested an F-350 pickup on the same 7% grade, pulling a 12,000-lb. fifth-wheel RV with 500 lb. of payload added in the bed. This really didn’t even scratch the surface of this truck’s true capabilities. The truck pulled the load up the grade at 65 mph with a little left in reserve. The Tow/Haul mode and engine brake made the service brakes unnecessary, except when tapping the pedal to demand a downshift.

The F-350's GCWR is 35,0000 lb. and it has a maximum fifth-wheel/gooseneck towing capacity of 26,700 lb.

Finally, it was time to test the F-250 through a 40-mile mountain loop that consisted of tight hairpin corners connected by grades up to 8%. Trailers were loaded with 9,000 lbs. With the Tow/Haul and engine brake engaged, this loop became an easy drive. On some grades it was simply necessary to tap the service-brake pedal to force a downshift from the transmission. Tow/Haul would then hold this gear. There was no noticeable trailer sway and output from the Power Stroke meant it was possible to briskly accelerate out of the switchbacks.

Overall, trailering with any 2015 Ford Super Duty leaves the impression of a smooth truck. There was none of the traditional "backslap" you can get when pulling a trailer, although we did experienced some occasional road lope. It is also obvious that Ford has worked hard at suppressing sound. While you knew there was a diesel under the hood, there was no clatter and the noise was subdued even when driving with the windows open to enjoy the fresh mountain air.

Fit and finish on the premium King Ranch and Platinum models that were available rivaled an upscale sedan. While I personally prefer the subdued looks of the Platinum model, I think the new color palette and leather used on the King Ranch is a visual improvement. The King Ranch leather is now a darker, richer color that fits well with the premium theme, while still garnering the attention of bystanders.

Increased capability and refinement coupled with the ability to instill confidence in conditions that could otherwise result in a white-knuckle experience sums up our experience with the 2015 Super Duty pickups.

Specs & Towing: 2015 Ford F Series Super Duty Pickups