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Page 1, Page 2, Page 3, Page 4 Squat Test
The trailer had a 10 percent (650-pound) tongue weight, which refers to the downward force applied by a trailer's own weight and cargo on the hitch ball. Measurements were taken before and after the tongue weight was applied to the truck. We measured the distance from the top of the trailer hitch ball mount “stinger” (that slid into the hitch receiver) down to the pavement. This test is important because the amount of perceived squat can impact the level of confidence drivers feel about their truck. Too much squat can make a truck look overburdened even if it’s still within its maximum towing or hauling ratings. These measurements were recorded without Ricardo Engineering’s participation. We were most interested in how the new Dodge Ram would perform, because of its innovative coil-spring multilink rear suspension. Chrysler says the setup saves up to 40 pounds of weight over a comparable leaf-spring setup, eliminates spring friction that can contribute to poor ride quality, and provides lateral as well as vertical control. Not surprisingly, the Ram had the most suspension travel, which allowed it to squat a full 3.6 inches from its static position.
Offroad Test
Similar to our hill-climb testing, we had a choice with our offroad test: run it in on a real-world trail or in a controlled setting. We opted for the offroad obstacle course at GM’s Milford Proving Grounds. The obstacle course had a quicksand-like gravel trap, a steep 75-foot-long, 46.6 percent dirt mound (a gain of 46.6 feet in elevation for every 100 feet traveled), and two telephone poles buried horizontally at progressive heights.
All the observations in this test were subjective. The GMC Sierra All Terrain was the first truck driven through the course. It drove through the gravel pit with minimal hop and fuss, then up the steep grade with plenty of power from its 6.2-liter V-8. We had difficulty, though, getting low-range four-wheel drive to engage. It took a few minutes of fussing in neutral and driving the truck a few feet backward and forward before 4-Low locked. The crawl down the hill allowed for adequate control. The Sierra was able to clear both buried poles without striking the frame, rocker panels or front air dam. The Chevrolet Silverado performed similarly to the Sierra, but with a few key differences. It was quieter through all the obstacles, and it scraped a bit at the top of the hill and some times over the second log.
The Dodge Ram started the trail by climbing smoothly out of the gravel pit, but when we started to tackle the 46.6 percent grade the engine stalled mysteriously. We weren’t able to repeat the stall with the Ram, nor did it happen with any of the other trucks. The Ram climbed the hill with good power and cleared the top without scraping. It had the lowest numerical crawl ratio of the tested trucks, and it whined the loudest as it descended the front part of the grade. The Ram climbed over both poles without scraping. The Titan was the best all-around truck through the offroad course. It required the least amount of orientation for the driver to operate the switchgear, which was placed intuitively next to the shifter. It was the easiest truck to get out of the gravel trap, and it made short work of both sides of the hill. It’s high ground clearance also made walking the truck over both buried poles an easy effort. The F-150 performed similarly to the Silverado. It had little difficulty getting out of the gravel pit, and climbing the hill only required a bit of extra throttle. There was scraping at the top of the mound that was repeated again over the second buried pole. The truck touched both points with the low third cross-member of its frame that hangs just below the bottom of the frame rails. The F-150 had the lowest and best-managed crawl down the steep side of the hill. Ramp-Travel Index
The test was simple. We used a single 20-degree, 36.5-percent-grade steel ramp at GM’s Milford Proving Grounds that was designed to measure wheel travel. First we measured the static distance between the bottom of the right rear fender and the top of the right rear tire when the truck was on level ground. Then we backed each truck up the ramp on the driver’s side to the point where the right rear tire started to lose contact with the ground. We then measured the now-extended difference between the bottom of the right rear fender and the top of the right rear tire. Backing each truck up the single ramp until the tire still on the ground lost traction was the best option we had for measuring wheel travel without dismantling each truck’s suspension and drooping on the bump stops. You’ll see in the pictures how compressed the rear driver-side tire was on the ramp side and how far the dropped passenger-side rear tire traveled, giving us a fair evaluation of wheel travel.
Another interesting observation about the Ram: The sleek, dual-pipe rear bumper exhaust system just missed touching the steel ramp at the truck’s highest point up the ramp. If you’re going to go off-road with the Ram, you’re best off with a Ram SLT or TRX4, which have standard single-pipe exhausts that exit below the right side of the bed. The Laramie only comes with the dual, straight rear pipes. The Toyota Tundra finished just a sixteenth of an inch behind the Dodge, and the offroad-optimized Nissan Titan took sixth place with just 5.75 inches of wheel travel. Two inches separated the first-place F-150 and the sixth-place Titan. Extreme Traction-Control Test
Traction control cuts engine power when it senses wheel slip, allowing the slipping wheel or wheels to slow enough for the rubber to once again grip the driving surface. It may also use the truck’s antilock braking system to brake the wheel that’s spinning, allowing the wheel on the other side to grip. Because most full-size pickups are rear-wheel drive but have the bulk of their weight positioned in the front half of the vehicle, they can lose traction more easily than other vehicles, particularly in icy conditions. The Ford F-150 and Toyota Tundra performed best. They were the only trucks to make it off the slippery surface without having to stop and engage four-wheel drive. The F-150’s traction was superior to the Tundra’s. While the F-150’s wheels did slip, the truck was able to cut throttle smoothly and apply selective braking until grip was restored and it was able to climb the basalt. The Tundra cut throttle too, but very aggressively. It took pushing the accelerator all the way to the floor to keep throttle up while the Tundra slowly crawled off the pad. Both the Tundra and F-150 had rear limited-slip differentials. They were also the heaviest trucks we tested, which likely helped. The Chevrolet Silverado and GMC Sierra both had locking mechanical rear differentials that engaged automatically when wheel slip hit a certain rpm. While both pickups performed excellently in the autocross, they were challenged by the wet surface and fishtailed backward as power was applied. We had to put both trucks into 4-High to get off the basalt. The Dodge Ram 1500 also required the use of 4-High to escape the split-mu surface, but like the F-150 and Tundra it has a rear limited-slip differential. To us, this was proof that extra weight and, particularly, excellent anti-slip logic can make a big difference getting a truck out of slick conditions. The Nissan Titan was the most challenged by this test. When its electronic-locking rear differential wasn’t engaged (which only happens in four-wheel drive) the rear diff operated as an open differential, meaning there was no way to shift power or lock up the slipping wheel. The engine quickly hit close to the redline as the Titan slipped backward and struggled to figure out a way off the hill before we cut power and engaged four-wheel drive to escape. We also tried several other traction control tests by driving the trucks straight up a wet jenite surface without stopping. Wet jenite has a coefficient of friction similar to an icy road. Almost all of the trucks were able to make it up the jenite as long as forward momentum was maintained at 10 mph or more. Again, the Nissan Titan was most challenged by this test and required backing off the jenite and using 4-High. Fuel Economy Test
We recorded the average combined mpg for each of the trucks and ranked them. All the trucks were filled up at the same gas station before we started the route and filled again at the end to measure how much fuel had been consumed. The Ford F-150 was the most fuel-efficient truck we drove, averaging 16.8 mpg. Considering it was also the heaviest truck, this was a remarkable achievement. Its new six-speed transmission, well-executed tow/haul mode, and fuel-saving features that cut gas as soon as drivers lift their foot off the pedal all contributed to this score; we’ve driven unloaded midsize trucks that can’t touch that number. The Toyota Tundra was just over a half mpg behind the F-150, at 16.26 mpg. The Tundra was the second-heaviest truck, but it has a much larger engine. We think the Tundra’s six-speed transmission played the biggest role in its fuel economy. The Dodge Ram and Nissan Titan were in a near dead heat, at 15.85 and 15.83 mpg, respectively. Not bad for five-speed transmissions, but still about 1 mpg below the F-150. Most surprising were the GM trucks. The Sierra and Silverado pulled up the back in the fifth and sixth spots, respectively, with their 6.2-liter V-8s. Those are powerful engines for pulling, but they’re mighty thirsty. The Sierra averaged 15.19 mpg, while the Silverado got 14.77 mpg. And to rub salt in the wounds, the GM trucks both required pricier 93 octane premium fuel to run at optimal power.
Tailgate Usability When you buy a truck, you want a tailgate that’s not going to be a hindrance. We closely examined each of the truck’s tailgates and assessed how functional and friendly they were to use. We gave the Ford F-150 our best review for tailgate functionality. It was the only truck that came equipped with a retractable step and pop-up handle that provided easy climb-in access into and out of the cargo box. However, we gave the F-150 low marks for the tailgate’s weight because that easy access came with a heavy price. One that required two hands to safely raise and lower the tail.
The rest of the trucks had standard tailgates, perfect for sitting on or extending the box length. The big differentiator was weight and assistance raising and lowering. The Nissan Titan’s tailgate had superior dampeners that required using only two fingers to raise or lower. The Tundra’s tailgate required only a little more effort than the Titan to move up or down and the Silverado, Sierra and Ram were all about the same, needing one arm to position.
Backup Cameras
The cameras were mounted in the bezels around the tailgate handle or integrated into the truck’s rear badge. Rearview video was displayed inside the cabin in either the rearview mirror or navigation screen, depending whether or not a navigation screen was in the truck. Our GM twins, the Silverado and Sierra, used both display solutions. The Silverado’s backup video appeared in the rearview mirror and the Sierra’s was shown in the GPS screen in the center stack. Though we liked looking level at the backup video in the rearview mirror, the much larger navigation view was easier to use.
The Dodge Ram and Toyota Tundra displayed video in their GPS screens like the Sierra. They were all about equal to each other in quality and driver assistance. |
