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Page 1, Page 2, Page 3, Page 4 Quarter-Mile Test
We rented the asphalt at Milan Dragway just outside Detroit to find out how fast and powerful the latest half-ton trucks are. The track features an IHRA-sanctioned quarter-mile dragstrip. It's perfect for determining performance over a fixed distance, unloaded and loaded.The tests we performed represent a reasonable scenario for drivers interested in learning how quickly they can accelerate up to 60 mph or more. These tests determine how well a pickup can join the flow of traffic on the freeway without holding up drivers behind them or causing an unsafe situation in a slow-moving vehicle towing a trailer.All the tests were conducted in two-wheel-drive at wide-open throttle with traction and stability control on. Tow-haul mode was engaged when towing and disabled when not towing. A minimum of three runs were carried out in each configuration tested. The average and fastest runs are presented in the results.In the pictures that accompany this story, you'll see the trucks racing each other. However, Ricardo Inc. only collected metrics and data from one truck at a time, using a $50,000 Oxford Technical Solutions RT3102 inertial and GPS recorder. How the trucks performed head-to-head isn't necessarily indicative of the final results you'll read about. We’re not sure who was more anxious, our team of journalists, starting the first set of tests for our biggest comparison yet, or the manufacturers in attendance, seeing all the 2009-model-year half-tons together for the first time. Quarter-Mile Unloaded Assessment
This year, the Tundra’s power ratings were pushed to third place (ranked by automaker; fourth if we rate by brand) behind GM’s 403-hp, 6.2-liter V-8 and Chrysler’s 390-hp, 5.7-liter V-8. Would the six-speed Silverado and Sierra be able to lay down all that power to the rear wheels through the 3.42 ring and pinion to beat the 4.30-equipped Tundra? Could the nine extra horses in the Dodge and its five-speed transmission outperform the Toyota’s six-speed shifting finesse using brute force? Unloaded, the Silverado was the fastest truck, beating the second-place Tundra by a scant .16 seconds and 1.5 mph. Two features gave the Chevy the edge: higher power ratings and shift points set to deliver peak torque at 4,300 rpm, which is 700 rpm higher than the Tundra. This proved critical in this test because all the trucks revved high into the 5,000 to 5,500 rpm range before upshifting and falling back to 4,400 to 4,700 rpm, which is near the sweet spot for the 6.2-liter V-8. One factor that reinforced our opinion of the Tundra’s unfriendly ride unloaded was a lot of noticeable vibration felt through the steering column and noticed in the interior plastic bits shaking as the Tundra raced down the track. The Tundra was the highest-mileage truck of the rigs we tested, with 8,000 miles on its odometer, versus approximately 1,000 miles for the rest of the test fleet, so perhaps it was showing a bit of wear and tear? The Silverado was very smooth the entire takeoff. The Sierra took third place, a razor-thin .04 seconds behind the Tundra, though 1.7 mph faster. The Sierra had the extra power and strength at the end, but its stiff offroad suspension likely contributed to its slower start versus the Chevy and Toyota. The Ram and Titan took fourth and fifth, respectively. They were the only trucks with five-speed transmissions. The Ram was quick off the line -- part of the inherent capability of its new coil-spring rear suspension to transmit power to the ground -- but the shift from first and second felt sluggish and played a role in making the Ram slower than the Titan through the first two-thirds of the quarter-mile. At the top of 2nd gear, entering 3rd, the Ram found its track legs and hammered home the final portion of the quarter-mile to beat the Titan by .16 seconds and 2.8 mph. We noticed some unusual behavior in the last-place F-150. Launching the truck cleanly proved difficult because we repeatedly encountered rear axle hop at wide-open throttle. We encountered this condition in only two places: on the sticky surface at Milan and again on an asphalt hill climb at GM’s proving grounds. We were unable to re-create the condition on public roads and highways. We believe it was due to axle wrap, possibly because the 6-inch-longer leaf springs on the 2009 F-150 allowed too much rebound. Once it was racing down the track, though, the F-150’s updated 5.4-liter engine and all-new transmission worked very well together. It felt really good -- until we started racing against someone else, at which point we quickly discovered how slow the truck was. Zero to 60 took almost 9 seconds, and it finished the quarter-mile a second later than the fifth-place Titan and 9 mph slower than the first-place Silverado. Quarter-Mile Loaded Assessment Hooking up a 6,500-pound trailer changed things up for the trucks, especially the GM trucks and the Tundra. With the extra weight on its tail, the Tundra settled down into an excellent power puller. The shift points in the transmission also changed, moving into the 3,400-3,700 rpm range at wide-open throttle, down from the mid-4,000s. This was closer to the Tundra’s low-3,600 rpm peak torque curve than the 4,300 rpm in the GM pickups. The Tundra’s 4.30 rear axle and lower combined drive ratios through all six gears helped the Tundra take off and keep its lead from start to finish. Still, the gap between the fastest and slowest of the Tundra and the GM trucks was only .36 seconds and .55 mph. We predict the GM trucks will be faster in this test in mid-2009, when GM adds a 3.73 rear axle option for the 6.2-liter V-8. This should make wide-open throttle launches easier for the GM pickups. The Nissan Titan and Dodge Ram paired up closely again, but the loaded Titan edged out the Ram by .36 seconds and .6 mph. The Ram was never able to recover from the steep 1st/2nd gear swap. The Ford F-150 lost its axle hop once the trailer was attached, but it also lost power. The 5.4-liter V-8 never broke the 70 mph barrier, like the other trucks did. The time gap between the F-150 and the fastest truck remained virtually the same during both runs, a constant 1.4 seconds slower than first place.
7.2 Percent Grade
There were two ways we could have performed our grade testing. The first was to find a challenging real-world incline, like the Cajon and Grapevine passes near Los Angeles, or the infamous 12-mile, 7 percent ascent to the Eisenhower Tunnel in Colorado. The alternative was to run our tests on the much shorter 7.2 percent hill climb at GM’s Milford Proving Grounds. Each percent is the equivalent of climbing 1 foot in elevation over a 100-foot distance, so we climbed 7.2 feet in elevation for every 100 feet the trucks and trailers traveled.
The 7.2 percent grade test was 1,720 feet, or 525 meters, long. That's 400 feet more than a quarter mile, which is 1,320 feet. All trucks and trailers were completely on the grade and stationary prior to the start of each run. All the tests were performed “brake-to-accelerator,” meaning the foot brake was fully depressed with the right foot, which then lifted and fully depressed the accelerator pedal in one movement. Sufficient distance was provided at the end to slow the rigs down to a safe speed before reaching the top of the hill. A minimum of three runs were carried out in each truck, with the same driver at wide-open throttle in two-wheel drive. We averaged the times from all of each truck’s runs to determine the best performer. The Silverado was the fastest pickup up the hill, but only by the slimmest of margins. It was tied with the Tundra through the first 430 feet; the trucks were so closely matched we could have passed our BlackBerries back and forth between them as we raced. The 3.42 ring-and-pinion Silverado finished its run just .14 seconds faster than the Tundra. We chalked up the razor-thin win to the Silverado’s 6.2-liter V-8’s extra displacement and old-school pushrod muscle over the Tundra’s sophisticated overhead-cam engine and 4.30 rear axle. The Sierra finished .73 seconds off the Silverado and .59 seconds back from the Tundra. The Tundra split the two GM trucks perhaps in part because of the Sierra’s stiffer suspension, though it could also have been normal performance variance between the two virtually identical GM pickups -- indicating any truck we test could have just had a bad day. The 3.92-equipped Dodge Ram did well. It finished only 1.08 seconds behind the Sierra. In fact, it was only a half-second behind the GM and Toyota pickups through the first 430 feet lugging the 6,500-pound sled, but as soon as it shifted into 2nd it lost momentum as the engine lugged against the relatively tall gear. It did beat the Titan, however, which topped the Ram during the level quarter-mile while pulling the trailer. The biggest surprise was the F-150. We suspected it might repeat its sixth-place finish from the level-ground tests, but instead it earned the fifth spot by edging out the Titan. The F-150’s traction control and tow/haul mode combined to out-finesse and hold peak power longer than the Titan. The Titan’s wheels had significant slip at launch, while the F-150’s had less than the Titan’s. Some axle-wrap showed up again, like it did during the level-ground unloaded testing, but it was a nuisance that disappeared soon after the F-150 started climbing. Also surprising was that the F-150 continued to coast up the hill -- not immediately lose power and momentum -- after we let off the accelerator. It’s part of Ford’s new torque converter lockup strategy that cuts off fuel but leaves the torque converter engaged longer to improve fuel economy.
Autocross
The answer is that we needed to push these trucks to the extreme to test their ride, handling and stability-control capabilities in slalom conditions, hard stops, 90- and 180-degree turns, and rapid, tight maneuvers. This provided an idea of how the trucks might react to emergency or adverse road conditions. In a world where cars and crossovers are getting smaller, it’s best if you can avoid these vehicles in critical situations, not run over them. A minimum of three runs were carried out in each truck, unloaded, by the same driver, in two-wheel drive with traction control enabled. The quickest lap time determined the best-performing truck. The Silverado and F-150 tied for the best time and highest speed through the autocross, at 48.64 seconds and 30.21 mph. The Silverado’s handling was deemed excellent, with only mild oversteer at the apex of turns under hard braking. There was slight body roll in the corners, but less so than in most of the other pickups. The Silverado’s braking was both very responsive and very aggressive.
We were surprised the Titan was only the third-fastest in the autocross, at 48.81 seconds and 30.11 mph. The chatter from almost every tester who flogged the Titan was that this truck felt the most confident of all the half-tons. Its seating position, ride height, visibility, power and braking made the Titan fun to drive around the cones. Handling was very good, with only mild understeer. In corners, the truck’s open rear differential (electronic locking) left one rear wheel spinning through tight turns, while acceleration coming out was nearly perfect. The brakes were very responsive and brought the Titan to a stop promptly. Some of us had very high expectations for the new Dodge Ram’s coil-spring rear running gear. The multilink suspension handles vertical and lateral forces with better control and less friction than the traditional leaf-spring rear ends the other pickups had. It turned out to be the fourth-fastest truck, at 48.94 seconds and 30.03 mph. The Ram handled similarly to the F-150 and Silverado, but with the most oversteer of the three. The front suspension dived noticeably entering the hardest curves. Surprisingly, it was a challenge on some of the corners to keep on the accelerator without the back end breaking loose. Braking felt similar to the F-150 and Silverado, and the steering felt remarkably close to the Silverado.
Most surprising of all was the GMC Sierra, which finished last. We thought its stiffer offroad shocks might give it an edge over the Silverado, but it turned out to be 2.2 seconds and 1.3 mph slower. Acceleration out of corners seemed delayed and sluggish at times. Braking was comparable to the F-150, Silverado and Ram.
Brake Test
It’s not surprising that the Toyota Tundra and Nissan Titan had the best braking scores. They have the largest brakes available in the segment, though the Tundra really stood out from all the other trucks; it stopped 7 feet shorter than the Titan.
The stopping distances of the second- and fifth-place trucks were only about 8 feet apart – incredibly close – versus a nearly 24-foot difference between the first- and sixth-place trucks.
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