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Big Dog Faceoff
Three New Trucks Compete to be our Clean Diesel Truck of the Year |
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A great tow rig will always be powerful. It will have more torque than horsepower, it will accelerate heavy loads without undue strain. It will get good mileage, and be comfortable to operate on long highway hauls. It won’t be cheap, so it’s got to look good and be well built. Of course, it will be a diesel. But which diesel? To find out how each of the three domestic one-ton pickups stacked up, we arranged for a brace of the newest diesels, all with ’08 compliant “clean diesel” powerplants. We took them to the dyno and the track. We did some heavy towing to find out what happens at the limit. We collected data that we weighed and tallied…which we present to you now.
The Trucks
Our field included three spanking new diesel test pickups, a Chevy 2500 HD, a Dodge Ram 2500, and a Ford Superduty F-350. All three run on ultra-low-sulfur diesel fuel, have single rear wheels, automatic transmissions and extended cab layouts. All three are 4x4s. All three have most, if not all, of the towing enhancements available from the factory, including class IV hitch. All three are comparably priced, give or take a few thousand bucks. And all three are impressively clean and smoke-free. Next problem was finding the right kind of load, keeping safety in mind. Class IV hitches are rated to pull up to 12,500 pounds with a weight-distributing hitch. Valley, the towing equipment company, stepped up and supplied us with a hitch rated for 10,000 pounds, to which we attached a 10,000-pound tow ball. With that weight in mind, we talked to our friends at Warrior Manufacturing, who kindly supplied us with a 30-foot, triple axle RV trailer. The trailer has drum brakes, making it fully compatible with factory brake controllers. The team at Warrior filled the trailer with fluids calculated to bring the weight up to about 10k, and they came pretty close. When we weighed the trailer at Cat certified scales, we ended up with 9,850 pounds—8,650 on the rear axle, 1,200 on the tongue. Our tow testing took us up what we came to call the Soledad Loop, a 35-mile round trip that climbed to 3,200 feet at the highest point, according to our Garmin GPS. It was a hot day, there was traffic to deal with, and the loop forced us to work the engine and the brakes, uphill and downhill, all the while hauling our 9,850-pound Warrior trailer. This part of our testing proved to be revealing indeed. K&N Engineering generously provided time on their SuperFlow dyno, expertly loading the dyno to extract consistent, comparable numbers. They ran the trucks for over three hours, making some 16 runs in all, in order to generate the horsepower and torque data you’ll see in this article. To get precise test numbers at the track, we used a GTech performance meter. It’s a triaxial accelerometer that readily gives us the accurate braking and acceleration numbers we were looking for. We tracked fuel economy across multiple fill-ups over a two-week period. We logged gallons, miles, cost, and location for each fill-up. The Ford and Chevy came with factory trailer brakes. The Dodge did not, so we installed an Odyssey brake controller, again provided by Valley, to even the playing field. If you had to do it yourself, cost would be about $160 bucks.
How We Scored It
To identify the best tow rig overall, we looked at performance and economy, plus four testers judged the trucks for interior comfort, exterior styling and utility, fit & finish, and overall towing ability. We tried to award points based on the relative value of the category, on a proportional scale. On the Dyno, every 10 hp was worth 1 point, and every 10 lb-ft of torque was worth 1 point. For the quarter-mile test, we gave the quickest car 25 points, and subtracted 1 point for each additional tenth (0.10) of a second. We used a similar system for the loaded 0-60 test, in which each additional tenth caused a one-point penalty. For mileage, we gave the best truck 25 points, and subtracted 1 point for every .25 mpg as efficiency decreased. For more detail on the scoring system, check My Two Cents, on page 6. Bottom line, we ended up with a points system that considered everything, but valued overall towing ability, torque production and mpg as the most important factors.
Ford Superduty: 446 Points
Ford built a 2008 Superduty specifically for this test and delivered it with 300 miles on the odometer. It’s actually our favorite truck, the one we prefer to be in most of the time. It has the best brakes, most comfortable interior, and the best fit & finish of the group. We think it has the best-looking exterior as well, though there was some debate on that. It also has some thoughtful features that make it a great work truck. These include power telescoping tow mirrors, a built-in brake controller, a bank of auxiliary switches and the unique tailgate step. The new Super Duty is powered by the 6.4 Power Stroke V-8. It’s a twin-turbo, intercooled powerplant rated at 350 hp and 650 lb-ft, backed by a 5-speed automatic transmission. It’s also the smallest engine of the three tested here, and on the dyno, made the least power. That said, it did put torque to the ground earlier than the other two, and its total, 539 lb-ft, is a good amount of grunt. When hooked up to the Warrior RV, it handled the load perfectly well, with good off-idle pulling power, but when pulling uphill at full throttle, it seemed to work harder and longer than the others at peak demand situations. On the track, it was slower to accelerate than the others, loaded and unloaded. The 6.4 is the smallest engine of the bunch, but we came to suspect the performance differences we measured were due more to the transmission, with only 5-speeds, than the engine itself. The Superduty has a solid front axle, great for strength, but with a trailer hooked up, we noticed that steering takes a little more attention. Yet the ride is not uncomfortable for a 1-ton truck, in fact, it might be the best of the three. The brakes are conspicuously strong and easy to manage, and the built-in controller is a nice feature. Set at 7, we had smooth stops with no jerk at the end. Instruments, while readily visible, are rather vaguely calibrated and disconcertingly lethargic. Upon start-up, the needles go to one spot and sit there, (other than boost) even when you know heat should be building. At one point, when we crested the Soledad summit, the fan clutch came on, yet the temp needle hadn’t moved from its start-up position. Possibly because the smaller engine had to work harder, the Ford averaged just a little better than 11 mpg overall, with a best tankful of 13.36 mpg and a worst of 8.27, which came after track testing and a long tow in heavy traffic. The lower fuel efficiency might again be due to the fact that the Ford has a 5-speed transmission, when the others are equipped with 6-speeds. Three testers noticed the transmission did not seem to permit direct access to 4th gear; mucking around with buttons never seemed to make us feel we could pick and choose from all five. The SuperDuty cleaned up in the subjective judging, winning the interior, exterior, and fit & finish categories. Testers felt great about the huge tow mirrors, the location and quality of the integrated brake controller, and the quality of the seats in the roomy cabin. It remains the truck we’d most like to tow IN, but not tow WITH, if you understand the difference. It’s a great ride, and a good tow rig, but not the best of the three when it comes to loads around 10,000 pounds.
Dodge Ram 2500 HD: 465 Points
Dodge gave us a bright red 2007-and-a-half 2500 HD with the new 6.7 Cummins under the hood. It arrived with 1,909 miles on the odometer. Let’s cut to the chase—it made the most torque earliest in the rev range, and was overwhelmingly judged to be the best pure tow rig of the bunch. The new Cummins 6.7 is clearly everything a Cummins engine ever was, maybe more. It has about 40 percent of its parts in common with the 5.9. The bottom end is amazingly heavily built, and while Dodge touts a 350,000 mile life-to-overhaul statistic, Cummins factory reps suggest the number should be more like 500,000 miles. Like the Ford, it’s SAE rated at 350 hp and 650 lb-ft, but the big Six makes peak torque at 1500 rpm, and more of it comes through to the ground. It uses a single variable-vane turbo, intercooler, and high-pressure commonrail fuel injection, and significantly, it’s the biggest engine of the three. On the K & N Dyno, the Cummins made a tick less horsepower than Chevy’s Duramax, and an equal amount of torque, but at lower rpm. We logged good mileage as well, averaging 14.47 mpg, with a best of 16.553 and a worst of 12.387. We didn’t test for emissions, but the Ram has a Bluetech emissions system, which the EPA rates as one of the cleanest diesels on the market. The emissions system is warranted for 120,000 miles. No urea injection is needed to meet EPA requirements in this GVWR range, but use of ULSD fuel is mandatory. According to a recent press release we found on the Chrysler website, you can run B20 in the Ram without any warranty concerns. Towing the Warrior RV, the Dodge loafed along with extra power in reserve. The gauges were reassuringly responsive, consistently showing increases in temp and pressure when working, although the temp gauge never recorded anything higher than 205°, at which point the fan clutch came on. Towing from a dead stop the Ram grunts into motion best of the three, using torque and a massive crankshaft to roll on power before the turbo even begins to spool up. On the highway, it doesn’t necessarily drop a gear when you ask for more speed—it just goes faster. And when you do floor it, the shift is smooth. At the same time, there were reasons why the Dodge was not the overall choice for best diesel tow rig. For one thing, the heavier Dodge did not brake as well as the other two when empty. True, when loaded, the exhaust brake made up for that, allowing slowing of heavy loads on offramps and downgrades without even touching the pedal. But just driving around, without a load, the Ram did not stop as well as the others, and overall, was exposed as the oldest design of the three. The Ram took a beating in the subjective scoring, where it was judged least appealing in the Interior category by a considerable margin. Ford’s emphasis on personal comfort and Chevy’s slick new cabin made the Ram seem dated by comparison, the cabin we’d least like to occupy for a 12-hour shift. The Exterior styling still gets respect from our old school judges, but a hood that did not fit well and a right rear door that didn’t like to close fully reminded us that this truck does not come from a new factory. So we found out the Ram is one serious pulling machine, period. If you have something serious to tow, and that’s what you really care about, this is your truck.
Silverado 2500 HD: 484 Points
Our Silverado 2500 HD, at $50,739 including destination charge, is the least expensive of the group, and the most versatile. We came to consider it the hot rod of the bunch. It is, fundamentally, a nice new truck, with an engine that can handle hard work, and a transmission to match. The Silverado’s 6.6 Duramax is SAE rated higher than the Cummins and Power Stroke, and backed it up on the dyno with higher peak horsepower than either of the others. When it came to torque, the Duramax exceeded the Cummins by just one lb-ft—essentially a push—although the Dodge did make its torque earlier in the rev range. The fact that the Duramax will make more top end power than either of the others makes it just slightly less of a workhorse, and just slightly more drivable in everyday circumstances. One tester observed that the Silverado might be a better car than truck. If that’s true, the Silverado is definitely a musclecar. It has tons of torque off the line, moves out readily and thanks to the Allison 6-speed, never seems to run out of breath. On the track, the Silverado was clearly fastest, and might have been faster if we hadn’t been running with 70 psi in the tires, which made it hard to hook up. Heavily loaded, the engine needed to build boost to move out, but once it got rolling there was enough power to pull our 9,850-pound Warrior RV to 60 mph the fastest of the three. When it came to towing on the open road, the Duramax had no problem with the load, although we all agreed that we would go with a Crew Cab/short box configuration, as the rear seating in the Extended Cab is not the equal of either the Ram or the Super Duty. The Allison provided better downhill compression braking than the Ford 5-speed, but did not match the Dodge exhaust brake on downhill sections of the Soledad grade. Even with the smallest discs in the group, brake pedal feel is good, and they are there when you need then. The built-in brake controller worked well set at 6.5, and overall, the truck feels a little quieter, with a little less wind and exhaust noise perceived. Could be that the absence of real towing mirrors—not included in the HD trailering package—worked with the Chevy’s narrower, cleaner wind profile to cut noise. However, once the trailer was in place, visibility was the worst of the three, forcing us to waggle the tail end to see what was behind us on the highway. With IFS up front, the Silverado had the most precise steering, with nice weighting and good directional stability. Pavement irregularities would pass under the front end unnoticed and register a little kick when the rock-hard 70-psi tires and heavily loaded back axle passed over. Fuel economy was surprisingly good for a V-8, something we attribute to a strong engine that operates well at part throttle, combined with a smartly programmed six-speed automatic. The Chevy’s mileage was consistent, with a best tankful of 14.798 mpg and worst, in traffic with A/C running, at 13.882 mpg. The Silverado got generally good, but not great, grades from our judges. The interior has a sophisticated look and feel, with clean lines and quality materials. It might have been the best of the bunch, but some testers felt the gauges were not as visible as they could have been, and that the radio was too low for comfortable access. When it came to fit and finish, careful examination of the paint revealed some orange peal, and a side molding that was just short of parallel. The bed came with cargo management rails, a nice touch unless you want to install a camper, and the spring-loaded tailgate got raves for ease of operation. The Silverado was the only truck of the three not to come with a bed liner treatment, which saved on the sticker price. Nitpicks aside, the Silverado dominated the empirical testing, and did well enough in everything else to outscore two good rigs. The Dodge can out-tow it, and the Ford might be more comfy, but in this Big Dog show, the Silverado is clearly Best of the Breed. |   The Ford Super Duty was considered the best looking of the test group, with the most comfortable interior and the fewest fit-and-finish issues. It also had the bestbrakes, and a thoughtufl array of utility features.
 Our test Ram 2500 is the truck with old-school good looks and the biggest engine around. While the truck itself is the oldest design of the three, the Cummins Ram remains the best pure tow rig.
 The Chevy made the most power and was fastest in all forms of track testing. In dyno testing, it was just a tick better than the Dodge. with a newly-revised interior, bold exterior styling and lots of upgraded features, the Silverado accumulated enough points to be our winner.
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 All three of our test vehicles had the newest, 2008-compliant clean diesel powerplants. The emissions control systems generally consist of a catalyst and a particulate filter, with each manufacturer showing slightly different construction methods. All three seemed to work extremely well, with nota whiff of smoke or diesel smell evident. |  Our test load turned out to weight 9,850 pounds according to the CAT truck scales. |  Our track testing included zero-to-sixty testing loaded with the trailer. The results generally mirrored the dyno and quarter-mile testing. We played around with the launches to get the best starts without hammering the hardware; too much throttle caused tire spin. |  The Dodge was a great truck to tow with, but definitely not as precisely built as the newest trucks. Sheet metal gaps, as this shot of the hood corner suggests, are larger and less regular. |  We checked fuel efficiency over a period of two weeks, buying and burning some 180 gallons of ULSD fuel, which is now widely available in California. We noticed none of the digital fuel readouts on the test units' "info centers" were accurate, generally suggesting better mileage than what the math proved. |  As you might expect, all of the interiors of our test vehicles were pretty nice, including the Dodge interior shown here. However, the other two trucks had nice touches the Dodge did not have, suc as built-in brake controllers and banks of auxillary switches. The Silverado interior was more sophisticated in style and execution, but the Ford interior was more comfortable. | |
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