2010 HD Quarter-Mile Acceleration Test (Unloaded)

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A significant part of our testing involved comparing all nine trucks head-to-head at wide open throttle, with and without heavy trailers. Why? HD pickups aren’t muscle cars, after all. At wide open throttle, we can measure the trucks at 100 percent of their maximum power ratings, something we can’t usually do for more than short periods when we’re on extended drive routes over public roads to grade ride and handling and fuel economy. It’s also one of the only ways to empirically separate the trucks’ performances from each other – which, in some cases as you’ll see, is only measured in the tenths of seconds.

Quarter-Mile Level Ground at Milan Dragway

We rented the asphalt at Milan Dragway, just outside Detroit. The track features an IHRA-sanctioned quarter-mile dragstrip. It's perfect for determining time and speed performance over a fixed distance, unloaded and loaded.

What's the point of running heavy-duty pickups through the quarter-mile? Isn't the job of a three-quarter or one-ton rig simply to deliver a heavy load or haul a trailer from Point A to Point B? You'd be correct, except for the one circumstance where the quarter-mile test almost always comes in as a handy measurement: merging into highway traffic from an on-ramp.

All the tests were conducted in two-wheel drive at wide open throttle, with the air conditioning turned off and with traction and stability control turned on when available. Stability and traction control is not available for Ram HD pickups and one-ton GMC Sierra Denali. The same driver was used for all the runs.

Tow/haul mode was engaged when towing and disabled when not. A minimum of three runs were carried out in each configuration tested. The fastest runs are presented in the results below.

It’s worth noting that in the pictures that accompany this story, you'll see the trucks racing each other; however, Ricardo collected metrics and data one truck at a time.

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 nine trucks together.

Three-Quarter-Ton Gas Trucks

As we’ve mentioned, it’s not just diesel-powered HD pickups that have seen big changes for 2010. The Chevy, Ford and Ram HD gassers have also been improved or are all-new since our last HD Shootout. Anytime there’s change like this, we wonder if it still makes sense to spend up to approximately $8,000 more for a diesel engine plus a premium at the fuel pump for diesel over regular gasoline.

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Mechanically, all of the gas trucks we tested were as equivalent as we could make them except for the rear axle ratio. The rear axle ratio can make a big difference in towing performance. The higher the ratio, the faster the driveshaft turns and the sooner the driveshaft can transfer peak horsepower and torque from the engine to the rear wheels. The result, generally, is faster acceleration and higher towing capacity than a rear axle with a lower ratio. Over longer distances, the truck can also wind itself out because it will be undergeared at high speeds. You can also picture the same concept if you ride a multispeed bicycle. It’s easy to get moving in a low gear but you’ll quickly spin out of the optimal leverage range that gear provides unless you shift to a higher gear that’s better able to convert your torque to forward motion.

The Chevy and Ram HD pickups had 4.10 rear axles while the Ford had a 4.30, which would seem to give the Ford a bit of an advantage starting out the quarter-mile, especially towing.

Ford only offers a choice of a 3.73 or 4.30 rear axle. We wonder why Ford doesn’t offer a 4.10.

Three-Quarter-Ton Gassers, Unloaded Testing

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Even though the Ram HD didn’t have any electronic help for keeping the rear wheels from breaking loose, the combination of strong Hemi power, a tallish first gear and the best power-to-weight ratio of the group made it the easy seat-of-the-pants winner.

Additionally, because of the noted taller gearing, the Ram HD made it through the traps at the end of the quarter-mile in second gear. The GM and Ford challengers were in third, if not quickly looking for fourth.

It’s worth noting that even with a new traction control system, the Super Duty 6.2-liter V-8 was having all sorts of troubles keeping the rear wheels from spinning and hopping at the line. Modulating the starts off the line was quite difficult, as the TCS shuts everything down after sensing slip — like a light switch — then turns it fully back on when all is quiet. This means if your foot is still giving it too much gas, it’ll go right back into the bad axle hop to start the whole process over.

The Chevys were much less temperamental and much easier to modulate at or near full throttle. We rank the software program for the GM competitor as smarter and quicker to react than its Ford counterpart. GM should be recognized for the fine-grained intelligence of its TCS.

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The Ram 2500, with its 383-hp, 5.7-liter Hemi-powered V-8 that makes 400 pounds-feet of torque, was the dominant contender in the unloaded quarter-mile. From the moment we saw the Ram run against the Ford and Chevrolet trucks, we knew we wouldn’t need to look at hard data to determine the fastest truck at Milan. It consistently pulled ahead of the Blue Oval and Bowtie pickups each time it rumbled down the track.

In the zero-to-60 mph test, the Ram HD was more than a second faster than the 6.2-liter F-250, which has a scant 2 extra ponies and 5 more pounds-feet than the Ram, and 1.7 seconds faster than the 360-hp, 380-pounds-feet Silverado 2500.

At the end of the quarter-mile, the Ram was still more than a half-second faster than the Super Duty and a second faster than the Silverado.

We’re not fans of Chrysler’s five-speed automatic transmission -- which has large steps between cogs and started to show some weakness in the last half of the quarter-mile in the higher gears -- but the Hemi’s increased power ratings and 4.10 rear axle found the sweet spot for this gas powertrain and worked very well with the gearbox. The Ram HD was also the only gas truck we tested that didn’t have traction control, which likely helped it reach full power sooner without the worry of a computer defueling the engine at the wrong moment. The Ram 2500 was the lightest gas truck we tested, almost 200 pounds less than the Chevy and 620 pounds less than the Ford.

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In contrast to our last Shootout, when a 6.0-liter GMC Sierra 2500 with a six-speed V-8 was the fastest gas truck we tested, this time around the 6.0-liter Silverado clearly lagged in performance. With substantially less power than the Ford and Ram and gear parity with the Ford, the Chevy was simply outmatched by the two other trucks. GM needs to replace this engine or give it a major overhaul to stay competitive.

We’re a little underwhelmed with the two-valve Ford 6.2-liter’s performance, too. Development on this engine took nearly a decade because of fits and starts, so what’s been delivered seems a bit behind by modern standards. Any all-new engine in the HD segment should come with direct injection and four valves for improved fuel economy and power.

At the end of the quarter-mile, all of the trucks were within 3 mph of each other.

Three-Quarter-Ton Diesel Trucks

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Like the gas trucks we tested, the single-rear-wheel three-quarter-ton diesel pickups were as equivalent as we could make them except for the rear axle ratio.

Given their more powerful engines, it’s not surprising that all the manufacturers provided trucks with taller (numerically lower) final drive ratios for improved fuel economy while still maintaining high ceilings for towing and hauling.

The Chevy and Ram pickups had 3.73 rear axles while the Ford had a 3.55, which would seem to put the Ford at a bit of a disadvantage at launch.

Three-Quarter-Ton Diesels, Unloaded Testing

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We had a feeling this group would be the hot rods of this year’s Shootout, and we were right. Everything came down to how well they could handle getting and keeping power to rear wheels without too much slip.

Again, the Super Duty offered too much torque to the rear wheels and not enough computer control to keep it in line. The system still worked like a light switch, turning wheelspin on and off, unable to finesse. It should be noted that once the Power Stroke found its grip, usually somewhere around 60 feet after launch, most of the push you feel is in the seatback. When the turbo kicks in, you feel it, and it pulled through the finish line. Like the 6.0-liter Silverado, the Duramax Chevy was smooth off the line, without any perceived axle hop and shot down the track. The new rear suspension geometry and wider asymmetrical leaf spring design was able handle everything the new Duramax threw at the rear axle.

The only place the GM diesel seemed to fall down was in the upper gears, shifting up to fourth gear, effectively stopping its pulling, through the 1,320-foot marker.

The Ram HD, although clearly a torque monster off the line, seemed to run out of breath once it was up and running down the track. It just seemed to stop breathing, as one might expect for a Cummins-B oil burner, to stop pushing at upshifting too early. Still, there was a steady and strong feel down the track. Maybe more than any other group on our test, each of these trucks had very different ways of getting to the finish: Ford’s was slow at start with a strong push through the middle and end; Chevy always had great launches but tapers off near the end; and the Ram HD pulled strong and steady but runs out of breath rather early. Maybe it’s not too surprising their finish times were relatively close.

We suspected that the performance of the new 397-hp, 765-pounds-feet Duramax V-8 and 390-hp, 735-pounds-feet Power Stroke V-8 were going to be tight, but we were surprised at how close all the unloaded three-quarter-ton diesel pickups were -- especially considering the diesels' radically different engine architectures. They were so close that it’s almost impossible to say one truck was materially better than the other two. The Ram 2500 with the 350-hp, 650-pounds-feet engine was the fastest truck we tested in the same scenario in 2007, and it performed spectacularly again this time, even though power levels haven’t changed.

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As you can see in the graph, a scant 0.2 seconds separated the fastest from the slowest over the full 1,320 feet. The Chevy clocked in at only 16.9 seconds while the Ram and Ford tied each other at 17.1 seconds.

The Silverado 2500 showed off its rear axle and power advantage over the Ford F-250 in zero-to-60 times. It took only 8.7 seconds for the Silverado to hit 60 mph. It took the F-250 9 seconds and the Ram 9.3 seconds.

While GM’s HD pickup didn’t have as big a weight advantage over the Ford as it did during out last Shootout – GM added about 300 pounds to the frame for 2011 when it changed from C-channel to fully boxed – it’s still lighter than the Ford by almost 300 pounds. Ford has dropped some weight from its diesel pickups since 2007, including 160 pounds in engine weight by shifting from the 6.4-liter V-8 to the new 6.7-liter V-8.

By the time we finished this test, we knew it would only be with heavy trailers that we’d be able to truly separate those trucks with the best combination of engine power and shift finesse.

One-Ton Diesel Trucks

The one-ton dual-rear-wheel trucks we tested at Milan were as equivalent as could be, down to the rear axle ratios, which were all set at 3.73. To make the towing test more challenging for the brawniest haulers, we used a 12,000-pound trailer. Each vehicle is equipped with the same engine and transmission as its three-quarter-ton diesel counterpart, but each gets unique rear axle setup, as well as weight distribution and tire options. Overall, each is carrying 600 to 700 more pounds of curb weight.

One-Ton Diesels, Unloaded Testing

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On the track, these trucks got all the looks. What probably surprised us most was the fact that even with a little extra weight, some wider flares and an extra set of rear tires, these trucks still ran hard and strong. Sure, this type of test was completely outside of their intended design envelope, but the info and data were telling. Even with DRWs, extra weight and a modified version of traction control, rear axle hop remained a problem, while the extra weight and more tires to help grip the track surface seemed to help the GMC Denali get better launches.

Torque braking the vehicles seemed to work best, but each one-ton had to be disciplined in different ways. The Ford couldn’t handle a full throttle takeoff any better than the Ram HD; the difference was that the Ford would go into a good hop, then get shut down by the traction control system, while the Cummins could just sit at the start line spinning the four rears all day long, sending plumes of smoke into the sky. All the GMC needed was the slightest modulating of the accelerator at the start to keep the wheels from spinning too quick, then the grip would kick in, and then it was just point-and-shoot at wide open throttle.

We also noticed Ford has built in a slightly longer throttle hesitation than the other brands, we’re guessing to allow the other inputs in the computer system to have their say as well. When all is clear, it seems to eventually allow for its slingshot takeoff.

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As one might expect, the results of the one-ton empty runs were a touch longer than their three-quarter-ton brothers, but only for the Ram HD and Ford Super Duty. To our surprise, the GMC Denali dually actually ran faster in both zero-to-60 times and quarter-mile than its lighter three-quarter-ton partner. In fact, the Denali ran 0.4 seconds faster to 60 mph at 8.3 seconds, and 0.3 seconds faster in the quarter-mile at 16.6 seconds. At 9.4 seconds, the Ford ran about a second faster than the Ram HD to 60 mph, while the Super Duty timed through the 1,320-foot mark at 17.4 seconds and the Ram HD at 18.0 seconds flat.

As mentioned earlier, each of the unloaded vehicles was tested without tow/haul mode enabled, so the engines, especially in the Cummins, seemed to run out of breath shortly after any shift. Our guess is that we could have squeaked out a few tenths in each of the competitors by running the empty trucks in tow/haul mode and maybe even playing with their respective four-wheel-drive systems for better launches. But we’ll leave that for another test.

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Comments

Not surprised, go GM!!! What do the FORD Girls have to say now, lol.

Surprised how well the HEMI performed even with the 5 cogger behind it.

Cummins did well too given it power disadvantage

Ford gas is .6 faster the GM gas 0-60 and .4 seconds faster in the quarter mile. The GM diesel is half a second faster 0-60 and a 1/10! of a second faster in the 1/4 mile than the Ford diesel. No surprise they are this close.

Should these tests make up over half the shootout when the results are so close? I don't know about anyone else but being 1/10 of second faster or .6 seconds faster down a tack isn't what I look for in a work truck.

Again, no surprise. Maybe the surprise is that is no surprises?

I'm a GM guy myself but i wouldn't diss the ford fans tho. The new super duty thats being unveiled soon will have 400 hp and 800 torque. A real competitor, can't wait to see the numbers on that beast.

No surprise the Cummins got its a** handed to it.

Looks like Ford needs to work on its traction control system and chassis.

Amazing Cummins 3 year old design tied in 1/4 mile with Fords brand new engine with more power( on paper). Love the new GM power to the ground numbers.

What concerns me the most about the GM is the inconsistency of the build quality indicated by the faster times and equivalent MPH posted by the dually.

When my fleet was all GM, we would get mileage averages from 9 to 16 mpg with the same driver over the same route - looks like they have yet to tighten up their quality control.

Plus - power to the ground is only part of the equation - towing uphill usually lasts longer than 20 seconds - how do these trucks handle foot to the floor for 5 min or more? Real world testing would be more informative.

The Cummins also has a 6 cyl. while the other 2 are V-8's.
How many people leave their diesels stock? Not many.
All 3 are good trucks. But will they last as long as the payments? The prices are out of site rediculious.

What I find mind boggling is that if you compare the Chevy's gasser performance in this shootout to the GMCs gasser performance in the 2007 shoot out, the older GMC performed MUCH better than this year's Chevy. CAN ANYONE EXPLAIN?? I dont think a heavier beefier frame would make that much difference and its essentially the same engine.

chevy on 20S inch wheel, not broken in, maybe that explain the difference

I think it is interesting to compare the quarter mile loaded and unloaded times of the gas trucks from the 2007 shoot out to this one. It appears that in 2007 the GM gas truck had a faster time and speed than any gas truck in this shoot out and it did it with a higher geared rearend and lower hp and torque numbers than the new GM HD's have. How is it that GM can increase the HP and torque and add a lower geared rear end and make the truck slower. It does not make sense.

I think IMO that they are somehow holding back the Ram HD gasser 0-60 and 1/4 times. Because in the MotorWeek video on this very website shows the same exact truck doing 0-60 in 7.2 sec. and 1/4 mile in 15.4 sec. Both numbers are a second and a half faster than pickuptrucks testing. No way same truck can be that much different. Im calling driver error in this test.

few years ago in the shootout you said that dodge needed to use a different automatic, like the ones they put in their heavier trucks. The transmission manufacture was not dodge, but a commercial transmission builder like Allison. Did they change transmissions?



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