2011 Heavy-Duty Hurt Locker: Quarter-Mile Loaded

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Words by Mike Levine, Mark Williams and Kent Sundling, Photos by Ian Merritt

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Testing

We carefully chose a combination of real-world and closed-course locations to test the trucks. We used our own GPS-based Racelogic VBOX test kit to record performance and geographic data.

A significant part of our testing involved comparing all three trucks head to head at wide open throttle, with and without the heavy trailers. Why would we do that? 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. It’s also one of the only ways to empirically separate the trucks’ performances from each other – which, you’ll see, is measured in the tenths of seconds.

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We traveled to Chrysler’s Arizona Proving Grounds (formerly owned by Ford) in Yucca, Ariz., about halfway between Kingman and Lake Havasu City. There, we set up camp on a multiple-acre stretch of flat tarmac. 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 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.

Acceleration Tests

Because of strong winds, we measured zero-to-50-mph times while towing trailers and zero-to-60 times when the trucks were empty.

There were headwinds from the south gusting 15 mph to 25 mph. To account for this, we ran each truck six times – three sets of back-to-back runs in north and south directions. We averaged each north-south pair to calculate the acceleration times and are presenting the time and speed of the fastest sets.

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Weather conditions recorded at Chrysler's Arizona Proving Grounds on July 13, 2011. The blue lines indicates each truck's testing start time.

For all testing, the same driver sat behind the wheel. Traction control was turned on and air conditioning was off, for maximum performance. Tow/haul mode was on when the trucks were loaded and off when they were empty. The exhaust brakes on both the Ram and GM trucks were also enabled when loaded. The Ford’s exhaust brake is automatically enabled when the truck is in tow/haul mode. Towing mirrors were at full extension or in the trailer-towing position when we towed and retracted or folded down when empty. Acceleration runs started by lifting the right foot off the brake pedal and pressing the accelerator instead of holding the brake down to build up engine rpm before launching.

Even though we had three identical new trailers behind the trucks, only one trailer was used for testing to reduce variables.

Towing Trailers

The Ford F-350 was the fastest truck through the quarter-mile when pulling a trailer, but just barely. It ran 1,320 feet in 25.63 seconds at 55.13 mph, almost a quarter-second faster than the GMC Sierra 3500, even though the Sierra finished with a higher speed of 56.75 mph. The speed and time charts show why.

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The Ford F-350 carried a higher speed through the first 600 feet before the Sierra 3500 started to outpower it, but by then it was too late. The Sierra couldn’t close the gap between the two, even though the gap was shrinking.

The Ram 3500 demonstrated a consistent pattern throughout all of the acceleration testing, which we could also feel by the seat of our pants. Hitting its peak torque at 100 rpm sooner than its competitors and its 4.10 rear axle helped give the Ram fast starts off the line – usually first or second through the first 400 feet – but its lack of horsepower seemed to hurt the Ram over the full quarter-mile. It finished the distance in 26.39 seconds at 53.46 mph. Overall, the Ram stuck very close to the Ford and GMC one-tons.

The Ford Super Duty’s coolant temps ranged between 208 and 219 degrees, and transmission temps hovered around 207. The F-350’s transmission was able to shift to 4th gear, finishing the runs at about 2,900 rpm, about 100 rpm above peak horsepower. We didn’t encounter any rear axle hop like we have in the past, but we could feel a surge of power move from the front of the truck to the rear as it launched in wide open throttle. In general, the Super Duty’s six-speed had the smoothest shifts of the trucks – something we also saw in performance tests and highway driving.

Gooseneck-hitch

The Sierra’s coolant temp stayed a consistent 210 degrees while transmission temperatures rose from 158 on the first run to 189 at the end of the third. A cooling fan kicked in whenever coolant went above 210 degrees until that target temp was reached. The Sierra held onto 1st gear the longest of the trucks, holding it until 3,000 rpm before upshifting to 2nd. It was the only truck that made it to 5th gear at the quarter-mile mark, upshifting at 3,200 rpm in 4th and immediately dropping to 2,300 rpm in 5th.

The Ram HD’s coolant ranged between 204 and 222 degrees, but the truck’s fan turned on in the low 220s and efficiently lowered the temperature to 210 in a few moments. Gearbox heat ranged from 199 degrees during the first run to 215 after the last. In general, rpm numbers from the Ram’s inline-six were lower than its eight-cylinder competitors. The Ram made it to 4th gear in the quarter-mile. There were occasional hard upshifts.

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Comments

I love me some blue oval.

Mike,
You say the Ram kept the coolest temps but it doesnt look like it from the data on this test. Do you mean overall throughout the entire test?

@smtrthnu: Which paragraph are you looking at? The Ram 3500 we tested had the best engine and transmission cooling performance of any late-model Ram HD we've tested in the last few years. Kudos to Chrysler for a job well done with the Max Tow Package.

Interesting how the F350 outpulled the Sierra at lower speeds. Seems to show the difference between tuned for torque and tuned for HP.
It would seem to explain why most of the work guys I know prefer the Ram or Ford. More torque and pulling power down low.

Such great detail! Awesome job, as usual, guys!!!

nevermined

How did the chevy hit 5th gear at 56 mph, that doesnt sound right. 4th gear at 3200 rpm is about 80 mph

Why test for just a quarter mile? Nobody tows just a quarter mile. Should have tested up a 3 mile mountain instead. This is a poor comparison.

Greg, have you read the other 9 pages of the test? There are two pulls up different grades.
http://special-reports.pickuptrucks.com/2011-heavy-duty-hurt-locker-performance/

@Greg: Read the 11-mile climb up Davis Dan and 7-mile climb up Eisenhower Pass and get back to me. Thanks.

http://special-reports.pickuptrucks.com/2011/08/2011-heavy-duty-hurt-locker-davis-dam-grade-climb.html

http://special-reports.pickuptrucks.com/2011/08/2011-heavy-duty-hurt-locker-eisenhower-pass-climb.html

The comments about Ford being able to outpull right off the bottom are being way over thought. Ford has a more powerful engine. What's the big mystery? Have we already forgotten the GM is out-torqued by the others?

For such small performance differences between Ford and GM (aside from hillclimbs) pointing out how a more powerful truck has more muscle off the line is stating the obvious and not worth the analysis.

@ Mike Levine

Must be frustrating how a lot of people come here leaving complaints before they read the article.

Dave, Stop being defensive. Ford won this competition.

@Dave: There is more than straight torque and HP. As the report shows, shift mapping and transmissions play a large deal. There is also tire size, tread pattern, inflation, weight, and material. There is vehicle weight and aerodynamics. Transfer cases. Turbo tuning. The list goes on and on...

My largest complaint is that they didn't run the same tires on all vehicles.

@Dave - I was commenting on the difference between torque and horsepower. The GM seems to pull harder higher up which usually indicates a horsepower advantage. A truck that pulls down low indicates a torque advantage.

If I spent more time on the highway I'd be inclined to go with the DMax Sierra. It pulls better than the other 2 at highway speeds.
I spend most of my recreational time on gravel roads. The speeds I hit are usually in the 40 mph range. That would seem to give the advantage to the Ford. The Ram seems to split the difference between the Ford and GMC down low.

I made the comment that most of the loggers I know drive either a Ford or Ram. That would fit the data shown. If you want pulling power down low - go with the Ford or Ram.
(I'll bet I'll get flamed by the GM guys for that comment but how can you dispute that fact?)

I'd love to see a gravel road/poor traction test with a heavy load.

The reason for the low speed performance of the Ford is simple.
It has a huge numericial gearing advantage in 1st and 2nd gear. In fact it has a advantatge in every gear, but it gets smaller as the trucks progress thru the gears.

Ford final ratio 3.73X 1st gear 3.97=14.80 X 800 TQ=11,840
GMC final ratio3.73X 1st gear 3.10=11.56X765 TQ=8,843

Ford final ratio 3.73X 2nd gear 2.32 =8.65X800 TQ=6,920
GMC final ratio 3.73X 2nd gear 1.81=6.75X765 TQ=5,163

As you can see the Ford has a HUGE advantage in those gears.
It is quite apparent that this is the reason if you look at the breakdowns in the acceleration tests. The GMC was faster as it progressed thru the gears. And it was the fastest in 30 to 50 MPH.
I am only surprised that with such a huge numericial advantage that the Ford didn't do better or said another way. How well the GMC did with such a huge disadvantage.

This is not to disparge the ford in any way. The tranny/motor package is what it is. But rathr to point out that it's not the motor that caused these results. Despite the ratings. The Dmax may very well be the stronger motor.

@Martin - excellent point.
Wouldn't lower gears benefit the motor that revs the highest?
It still supports my belief that if I were to buy a HD and spent most of my time on the highway - the DMax Sierra would be the better choice,
but if one spent more time pulling heavy at lower speeds - the Ford would be the better choice.

Well, I really doubt that the Ford could actually use all that torque on gravel or dirt roads. There just wouldn't be enough traction avaliable.

I tow 14-15K on the highway to where I turn off onto such roads to get to my camping spots. Lack of power on these roads has never crossed my mind. It just isn't a problem.

@ martin...I am glad you pointed that out cuz my 10 month old could have looked at the Trans gearing and figured it out...I was about to respond when I seen your comment (allthough not is as much detail).....tuned for torque vs tuned for HP....LOL

Great job on the testing. The results of the quarter mile tests within the first 600 feet is the result of the vehicles 1st and 2nd gear ratios and final ratios more so than the available torque and horse power.

John,
I agree, I've been trying to figure out how the GMC hit 5th gear while the Ford was in 4th at 2900RPM. The GMC shifted from 4th at 3200RPM. I understand the GMC was moving fast than the ford at that point in time, but with taller gear ratios all the way up, if it hit 5th it should have been moving a whole lot faster than the Ford...could the GMC have just hit 4th gear when it finished the quarter? With the taller gears and the power up top I could understand the GMC revved out in 3rd while the Ford was pulling in 4th.

A while back an automotive engineer commented that he fealth that the Ford would of done better on the highway with taller gears, not lower gears. That is an interesting theory.

I have to disagree with Lou analysis of the rear wheel power. When calculating rear whel power you have to calculate the power not the torque. In order to do so you need to consider the RPM and know the given HP and Torque at that given RPM. Then you can multiply the power behind the engine by the final drive but this is only valid when the torque converter is engaged i.e. usually at highway speed which is never the case at wide open throtle. The torque converter and transmision shift mapping clutch gripping strenght have a lot to do with rear drive performance and furthermore some engines will be electronically controlled (read chocked) to respect emission control and prevent components damage. I am a proud RAM high ouput owner and choose so for engine durability.

hey mike. you should test diesel trucks from the 90s generations. just to see who was best in the good old days

i find this article a great work on consumer behaviour and the approach we take for our business set ups. i am looking forward to the upcomming book of the author. i applied some of the principles in my business approach.



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