2010 HD 7 Percent Hill Climb Test

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The 7.2 percent grade test was a 1,600-foot steady grade. That's 280 feet longer than the quarter-mile test we performed on the flat ground at Milan Dragway.

The trucks were only tested pulling trailers – 10,000 pounds for the three-quarter-ton gas and diesels, and 12,000 pounds for the one-ton diesels.

All trucks and trailers were completely on the grade and stationary before 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 (after the 1,600-foot mark) to slow the rigs down to a safe speed before reaching the top of the hill.

At least three runs were carried out in each truck, with the same driver behind the wheel running at wide open throttle in two-wheel drive. Stability and traction control were turned on in the Ford and GM trucks; Ram pickups don’t offer stability control. Tow/haul mode was enabled in all trucks.

The fastest run for each truck is included in the results below.

Three-Quarter-Ton Gas Trucks Towing 10,000-Pound Trailer

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A new feature that’s available for both the Ford and GM HD trucks is hill-hold assist. Originally conceived to help vehicles with manual transmissions start out on steep hills without needing to use the parking brake or put extra wear on the clutch, hill-hold assist automatically applies the vehicle's brakes for 1.5 seconds to 2.5 seconds (depending on manufacturer) once you lift your foot off the brake when you're on an incline that’s at least 5 percent. It's also part of the trucks’ integrated trailer brake controllers, so it will apply the trailer's brakes, too, if it has electric brakes.

While Ford and GM no longer offer manual transmissions for their HD pickups, we still found the feature useful starting the hill climb from a full stop with both truck and trailer on the grade – when it worked. It didn’t on the GM pickups, which was traced back to a glitch in the hill-hold assist calibrations on the 7.2 percent grade only. That issue has already been fixed in production.

Adding gravity made the contest much more interesting for the gas trucks. When you look at the performance numbers and truck specs, there's some high drama happening among these haulers.

The Ford F-250 and Ram 2500 were neck and neck through the first quarter of the hill climb. At the 400-foot mark, they were within 1 mph of each other. As the Ram upshifted into second gear, its awesome Hemi V-8 wasn’t enough to make up for the large step between cogs. It seemed to flat-line in performance. That gave the Silverado the opening it needed to finish close in performance to the F-250, pushing the Ram to third.

Whether by design or by nature, we really liked the way the Ford 6.2-liter seemed to come to life on the hill. It sounded great in the Super Duty, as if we were driving a high-horsepower Mustang at the dragstrip.

Three-Quarter-Ton Diesel Trucks Towing 10,000-Pound Trailer

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The Ford and GM diesels dominated on the 7 percent climb. It was an awesome display of greater firepower and six-speed flexibility that put the Power Stroke and Duramax rigs onto a different playing field altogether. Not even the Cummins’ earlier peak torque – at 100 rpm lower than the Ford and GM trucks – gave it an advantage.

By the end of the grade, the Silverado 2500 was 5.8 mph and 3.4 seconds faster than the Ram, and it was 1.9 mph and 1.8 seconds quicker than the Ford.

The Ram may have the advantage of not requiring urea for its diesel engine, but we think many diesel owners would gladly trade that maintenance item for the huge advantage in performance.

However, we can’t forget to point out that the well-equipped Ram is almost $8,000 cheaper than the Ford and Chevy trucks. Certainly for that bargain price, and with its handsome interior and exterior styling, we could be persuaded to opt for the Ram. So what if you don’t get to the top of the hill the quickest?

One-Ton Diesel Trucks Towing 12,000-Pound Trailer

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The fastest one-ton truck up the hill was the Ford F-350, just a tenth of a second faster than the GMC Sierra Denali 3500HD and 3.7 seconds faster than the Ram.

While the Ford F-350 consistently shifted all the way up to fourth gear at least 100 feet before the end of the run, the Sierra Denali and Ram only made it to third gear. The Ford shifted into fourth at 3,200 rpm while the Denali hung onto third, just over 3,000 rpm. The Ram, which ended the run at 46 mph, was at around 2,700 rpm.

We think the F-350’s shifting into fourth gear so quickly on the grade is one part of Ford’s fuel economy strategy, to return up to 20 percent better fuel economy than the Super Duty used to get with the 2008-10 6.4-liter Power Stroke diesel.

Torque-converter lockup strategies were also interesting to observe. A torque-converter lockup clutch is an automatic mechanism that helps match engine and transmission speeds during acceleration for improved shifting efficiency and fuel economy. As we ran up the hill, engine rpm in all the trucks would steadily climb and then fall back slightly as their torque converters slipped. The Ford locked up in third gear, just before fourth and the Denali locked up in second gear, just before third. We couldn’t tell when the torque converter locked up in the Ram.

While the Sierra Denali’s launches were always clean, the upshift from second to third was consistently a bit harsh. The Ford exhibited some rear-wheel hop, even though it was a dually with 12,000 pounds hanging off its bumper.

We noticed interesting transmission temperature variations among the three trucks. The GM trucks typically had the lowest temps, from 174 to 196 degrees; the Ford Super Dutys consistently stayed within a remarkably tight band, from 196 to 198 degrees; and the Ram pickups ran the hottest and climbed in temperature the fastest, from 178 to 208 degrees.

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Comments

What happened to the Gm 3/4 ton speed at the 7th mark. It actually lost speed? Geez even the Ram managed to keep accelerating up the hill.

The real question is, Would a person give up the extra cheese to buy a GM or Ford for the little performance gained over the Ram? Especially in 2500 garb.

Anyone notice in the video how far the rear-ends on 3/4 ton SRW Dodge and Ford dip on the uphill climb? and how straight and solid the Chevy rear-end looks?

Im loving this new frame from GM, I think its segment leading.

No surprise the Ford F-250 gas came in first.

No surprise the Ram diesel came in last. Some Ram guys may like not using diesel exhaust fluid but it gives up too much performance to the GM and Ford diesels in doing so.

No surprises.


The heavier the load, the better the ford engines do compared to the gm and dodge. I'm really excited about ford's new engines. I think they're a lot more capable than gm and dodge as far as upgrades go. My complaint about the HD shootout is that they didn't get the 400hp 800tq truck from ford. I wonder how big a difference that would make in the end results. I imagine motortrend or some other website will be testing all three trucks against each other soon with ford's upgraded engine. It will be interesting to see if they choose the ford as the winner. Popular mechanics chose the ford in their comparison with the version 1 diesel. anyway all the trucks are pretty close. I'd probably go with the cummins for its overall value and proven dependability.

@beebe - I suspect Ford's traction issues would be worse with more HP/Torque hitting the back wheels.
Ford's problem looks more like a chassis/traction control issue than a weak diesel engine.

@Mike Levine

Any reason why the graph data and the video of the 3500 7% grade don't match. It says that the Denali was 3 seconds slower than the f350 but the graph says it was .1 seconds slower. Also, it would seem that the MPH graph is completely flipped as the GMC is showing always having a higher mph but finished with a slower time. Something is wrong, just not sure what is right.

@vettelovralexand: Just checked the data again. Go with the graphs. It's based on time and speed data collected and supplied by Ricardo. The video was based on my commentary of the data and notes I took on the 7% grade. It appears on the video that I accidentally swapped speed differences between the Ford and Sierra. Sorry about that!

this is all bs and im a ford guy, why the hell does the ford and dodge sag, and the chevy dont, ford needs biggeer leafs or it jipped, PICKUPTRUCKS.COM IS A SCAM there qall good trucks but they can admit that fords ar best, and haul bigger loads better, chevys and dodge will always be behind ford in real world.

I don't have a dog in this fight - just a soon to be new truck owner of a good brand to pull my fifth-wheel. It is HIGHLY unusual that the Chevy 3500 was faster than the Ford F-350 at every point, yet the time was greater.

I have two degrees in engineering from decent schools, so the response that Ricardo is right is a little bit misleading.

It looks like the response time on the Chevy driver on the best run was slower than the Ford driver on the best run. The Chevy was behind by 0.74 seconds at the 200' mark.

Being as the Chevy made up 0.64 seconds of the 0.74 second gap over the last 1400 feet, I have a good idea which one would pull my fifth wheel up a grade marginally better. The differences between the Chevy and Ford are not significant enough to outweigh personal vehicle preferences and perceived reliability, however.

I'm watching reliability a lot more than performance. With all the gizmos added for the EPA, these could become expensive vehicles to own as they age.

@engsound: We're going back to Ricardo to check the original data file for the GMC 3500 and F-350 on the 7 percent grade. I was the driver during all of the 7 percent grade instrumented runs with a Ricardo engineer in the seat next to me to collect data and ensure consistency.

@Mike Levine: The numbers work out if there is that big of a discrepancy in the first 200 ft. But, I wonder if this data was taken when the GM rollback issue hadn't been fixed or if the Ford is actually that much stronger off the line despite its chassis/traction issues.

@vettelovralexand, @engsound: I just spoke to Ricardo about the 7% grade results for the F-350 and Sierra 3500. Here's the response about the runs shown.

"The Ford was faster to 200 ft by 0.74, then the GMC was playing catch up for the rest of the run. It ended up only 0.1 behind, so obviously quick once it got going, but the Ford was the quickest off the line."

Thanks for clearing things up Mike. I figured that was the case, but I appreciate you going the extra mile to answer any and all questions about the test data.

Same here - thanks for researching and finding the answer.

The main things I take away from these tests:

Ford has completely dominated the gas engine war - by probably a wider margin than the 2007 test even. In the 2007 test, the 6.0L Chevy was at least keeping up or gaining on the V10. This year - the 6.2L walks away at the beginning and keeps pulling away all the way to the end. I am only referring to the hillclimb towing tests - which is really the only time a HD truck has the pedal to the floor for an extended period.

I am not convinced that I "need" a diesel to pull my 10,000 lb fifth-wheel. I've been pulling it for years with my 6.0L gas 2002 Chevy 2500HD and have been content (even in the mountains). It doesn't set speed records, but given that it pulls a trailer uphill about 0.5% of its life - fine by me.

Among gassers, the Ford is really the only gas that would warrant my purchase. The Ford gas performs very similarly to the Dodge diesel and would be a worthy alternative to the Dodge diesel.

Dodge is massively out-gunned in the diesel war. It is sad to see what happens to a company when they have no resources to reinvest in their product line.

Ford versus Chevy diesel is down to whether you want a Ford or a Chevy. Real world driving would have a hard time distinguishing the performance difference.

@engsound,

Gas all the way.

I still got my V10. Best gas engine I have driven in a HD truck.

First thing, Dodge got a free pass to escape mandated Urea for a few months by using all saved carbon credits. That is fact. Dodge still offers a stick with the Cummins because the automatic usually fails at 100K miles or less. At a dismal 15% of the market share Dodge isn't really a player anyway. Dodge, by law, has to build Urea spec after all carbon credits are gone. Ford has produced, in house, 2 diesel V8's -6.0 and 6.4 that have been a nightmare in everyway. Short lived, horrible resale value, lawsuits and more. The 7.3 was a Navastar, Ford is betting hard the "new-ish" 6.7 Diesel will survive. 1 out of three ? sounds scary plus the worst warranty on the market. GM Duramax, over 1.2 million sold and climbing everyday. GM got rid of the stick transmission behind the Duramax because of failure due to too much torque. GM/Allison has the best 6 speed automatic, end of story. GMC and Chevy come with a standard 5/100,000 powertrain warranty, it is the best bet. Also Dodge pickups are not $8,000 less than GMC, Chevy or Ford. That is pure bull. In most cases the Dodge stickers and costs more by thousands. Urea is after the engine burn and part of tailpipe emissions, it has zero effect on performance ! Before anybody comments may I suggest that all this information is on the web, dig deep and you will find it. Thank you....

"Ford has produced, in house, 2 diesel V8's -6.0 and 6.4 that have been a nightmare in everyway" - American Patrick

You don't know what you are talking about.

Navistar produced them.

Dear mopar I love you but why isn't the largerhemi in the hds WTF the larger hemi would beat or come very close to the ford gasser and beat up the gm one and give cummins a call and demand a new version we all know a cummins will outlast a powerjoke and duraturd by far but cmon were prob losing sales and def bragging rights

It is pretty sad that you cant take a Ram of similar weight and classification, but that you have to take the Mega Cab which is a heavier truck making it not on the same playing field and it is still keeping up with the GM and Ford. I dont see what people have against the Ram trucks. They are excellent trucks and I would say much more reliable that the GM and Ford and have better standard features. PickupTrucks.com next time try to make the shootouts a little more even across the board and you will see that your GM is not superior than the Ram like you want people to believe it is.

@LinctheSink: If you'd take the time to read the first page of the Shootout, you'd see that all of the truck makers were given several weeks to choose the best truck to send to the Shootout. We *shared* the configurations with all of the manufacturers so there were no surprises. Chrysler *chose* to send a MegaCab truck.

Oh yeah, if you took the time to read the entire story, you'd also see the Ram MegaCab was the *lightest* one-ton truck we tested.

American Patrick, Ford did not build the 6.0 or the 6.4, navistar did. As for the transmission I would say that fords Torqueshift is doing a far beter job than the Allison. When these trucks were matched equal (3.73 rearends) the ford beat the duramax (when they were in 4x4) even though it had less hp & torque,(at that time) and now since ford has increased the hp & torque it will probably beat the DURAMAX with its 3.73 rearend against fords 3.55 rearend as they were in the f250 and gm 2500. If it wasnt for the wheels spinning the ford would have already

Anybody notice how close the performance is between the Ford 6.2L gas motor, and the 6.7L Cummins? Pretty impressive for a gasser!

Something is wrong with either the data, or the Silverado 2500 Duramax had some strange problem, since the chart shows that it actually SLOWED DOWN from 56.34mph at 1200ft., to 54.77mph at 1400ft. and even at 1600ft. it was supposedly still moving slightly slower (56.24mph) than it had been at 1200ft.

And supposedly it did this despite there being no trace of this slowdown in the time-to-distance chart. How did the Silverado 2500 Duramax actually slow down after the 1200-foot mark without having a corresponding increase in time?

The Chevy 2500 Duramax might have gained speed more slowly due to a transmission shift (and even that is doubtful) like the Dodge, but there is NO WAY it actually slowed down, unless there was something wrong with that truck.

The GMC 3500 Duramax has an identical powertrain (engine/trans./rear axle ratio), in a heavier dually truck, and was towing a heavier trailer, and there is not the slightest hint of that 'slow-down' anomaly in its chart.

I realize a lot of time has passed since this test, but what is up with that Silverado diesel 2500's drop in speed after the 1200-foot mark?

I'll out drive any ANY driver that you wish me to take on. YOUR DRIVERS REALLY SUCK FORD!
Please reply. or are you all CHICKEN!
Get ass whooped by a women and stuff. I can see why you are. you guys hire drivers that totally don't understand how to drive. "Nuff said."



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