Ultimate Three-Quarter-Ton HD Challenge: Braking

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To do brake testing properly, we needed a large, closed expanse of pavement all to ourselves. And there just aren't many of those around world that don't have a shopping mall attached to them. Thankfully we had the use of "Black Lake," a paved surface so large you can see it from space, at GM's Milford Proving Grounds in Michigan. It was here that we conducted our 60-to-zero empty and loaded brake-testing runs with our three three-quarter-ton gas-engine 4x4 pickups for our 2014 Ultimate Heavy-Duty Challenge.

 

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This particular event was all Chevrolet, at least in terms of stopping distances. When empty, the Silverado 2500 stopped in 3.4 seconds in 146.4 feet, while the Ford F-250 stopped a little faster (3.3 seconds) but over a slightly longer distance (147.8 feet). When loaded at max payload, the Chevy stopped in 3.4 seconds and 150.1 feet; the Ford in 3.3 seconds in 153.2 feet. The Ram 2500 didn't do well in either case, stopping in 155 feet when empty and 161 feet when fully loaded, both in 3.6 seconds.

How We Did the Testing

We used our bags of rock salt in the brake-testing area for the loaded runs with each competitor. For empty and loaded runs, we used the same two-person team strategy for each of the brake-test runs with one change. For this test we used one of our judges, Kent Sundling from MrTruck.com, because of his skill at knowing how much each truck's speedometer is slightly off — and they all seemed to be off by a little bit. In the passenger seat, RaceLogic VBOX expert Joe Lachovsky recorded all the data and monitored the actual speed of the vehicle based on satellite observations of our test gear, calling out the speed readings to Sundling so he knew exactly when they hit the target speed.

Each empty and loaded run went around (in a big loop) Black Lake, entering from the south side of the track. Slowing and gently squeezing the throttle, Sundling would get to the 60-mph mark then mash the brake pedal, holding it to the floor until our computer recorded the time and distance. If that sounds like fun to you, imagine doing the same thing about 20 times over the course of hours. After each disc-brake-heating foot stomp, there was a 1-to-2-minute mandatory cool-down drive around the pavement to make sure the front brake temperatures were within factory parameters.

Cars.com photos by Evan Sears

 

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Overview | Milan Dragway | Fuel Economy | Milford Hill Climb | Braking | Davis Dam | Eisenhower Pass | Results

Comments

"there was a 1-to-2-minute mandatory cool-down drive around the pavement to make sure the front brake temperatures were within factory parameters."

See this as feedback for something we would like to see in the future... try a few runs as back-to-back as is possible, it would be really nice to see how the trucks degrade as brake temps go up and fade kicks in. Stopping once is nice on paper, stopping the same way time after time is a whole lot more important.

Again, see this as constructive feedback... loving the test so far, 3 more pages to go.

This single stop test, is a test of the tire's traction, not the brake system's heat dissipation/thermal capacity.

Ram has the worst fuel economy, and worst braking.

Yes Dave, we can read.
The Ford had the tallest overall gearing, yet the Dodge had the tallest low speed (<70mph) gearing, Chevy-the shortest everywhere AND without cylinder shutoff.
We don't know the cold/hot tire pressures.

GM has always had the best brakes

Wtf?! I am patiently waiting for the usual suspect Fiat boy to tell us what a POS death trap the Fiat is since it stopped the worst!

I do think that shoot-outs should be done on the same tires. That would reduce traction variables attributed to tire choice.

Once again, the GM surprised me.

Nah, too expensive, and there would be arguments about what tire to use. You run what you brung.

It also wouldn't be real world unless you bought those same tires. Run what you brung.

Eleven feet is nothing. Every vehicle you get in and drive stops at a different distance than one you got out of, if you can't deal with eleven feet you should not be allowed to drive and dam sure should not be allowed to tow.

@Ramadan little Horn 1500 -

11 feet is nothing?

Really?

Didn't you say you were a cop?

Must of missed the class on car crash scene assessment.

I'd love to pile on the Super Duty but fact is tires can affect these differences, would be more interested in temps and fade as well as downhill towing brake temps at the bottom, TFLT does this and in the 3500's the Fords were always way higher than RAM and GM due to the better tow/haul, engine/turbo braking on the Diesels.


11 feet is nothing?

Really?

Didn't you say you were a cop?

Must of missed the class on car crash scene assessment.

Posted by: Lou_Bin laden | Aug 12, 2014 9:14:52 PM


Are trying to me every car and truck stops in the same distance?

Are you also trying to me that you are not capable of adjusting for what ever vehicle you are operating?

It might be time you turn in your drivers license.

I am going to update my brakes on my 2014 Power Wagon after adding my 37's. E.B.C or Baer or Brembo. :=)

Re the comment suggesting all the trucks use the same tires. Not a good idea. I want to know how the truck performs as it comes off the showroom floor, which is the way I drive it. I don't run out and trade perfectly good new tires when I buy a new vehicle. Just isn't going to happen for the vast majority of buyers. Therefore it's best to test the trucks as we will drive them.

@JRT: if we could find a particular tire that is the exact same size and type tire that is used by all three brands, why not?

Ok Dav, I will explain something to you. The possibility is that if the Ram had the AT tire, and the others were on a Good Year SSA which is a very highway oriented tire that would explain something possibly.

Have you ever heard of a thing called tread squirm, Dav? After all, you claim to be an autocrosser, I would think you had some sort of knowledge about that.

You cannot expect an AT tire to stop as good as a highway tread tire.

I might be wrong, but are these not the same brakes that the Rams had in the 2011 heavy duty shootout? In the case of that truck it out stopped the Chevy and the Ford both loaded and empty with a better stopping time then these posted here. Both the gasser and the diesel out stopped the other two brands in that shootout.

If you were to read about Diesel Power magazine's comparison of a 1500 diesel and a 2500 diesel they tested using a 2014 ram 2500 Laramie Longhorn crew cab 4 x 4, (a much heavier truck weighing in at 8000 pounds without the driver in it, and with much more weight on the front end, ie, the Cummins diesel, which gives it a much heavier ratio to the front which is not as desirable as a lighter front end) The truck had the Firestone Transforce HT tires (highway tread, as opposed to the other optional Firestone tire the Transforce AT tire) that truck stopped from 60 empty in 146.2 feet. They did not do a loaded down test but that's a good deal better stopping right there from a heavier truck, yes I know, it was a different test, a different driver, a different day, and a different location.

LOL Dav, The funny thing is, is that even this Ram 2500 with it's much heavier weight in it, darn near stopped better then your Tundra is tested in the 2013 light duty challenge! That's funny right there, I don't care who you are!

Toyota Tundra, the truck they claim is overbuilt, put a little bit of weight on it and it can't stop for nothing even with its street tires on it!!

Oh, I was referring to the three-quarter tons, because in the 1 ton dually trucks the Chevrolet clearly had that class won on brakes.

Also funny thing, people think that the Eisenhower test was a matter of braking, it was more than just a matter of braking it was also a matter of gearing but some of the Schmucks on here don't understand that at all.

I get a laugh out of the people going on and on about the tow haul how it makes the other models downshift to second gear, that's why I bought a truck in 2010 that had to be able to be put in any gear unlike Ford in 2010 which did not have select shift then. If I want to put the truck down in second gear I do so, on my own. I don't need computer systems to overmanage my truck for me. And if some of the smarty pants on here were to actually look at the gearing they'd realize the Chevy and Ford gearing help them out quite a bit right there. The Ram truly needs the eight speed or a six speed with much higher numerically gearset.

After all, I was the one telling these Ford fanboys that their Infamous 5.0 for 2011 to 2012 was not all that, it's just had a better ratio of transmission gears. Same with that turbocharged Ford gasser, the eco-bust. That truck clearly got it clock cleaned by a Ram in that light duty challenge.

Transmissions make a lot of difference, somebody tell that to Jason, he doesn't get it.

And yes George, I'd much rather have the truck go all the way through second gear and shift into third gear at the end of the 60 mph as opposed to the other truck being at 4700 RPM in 2nd, if I wanted the fastest truck out there. But there's more to the truck than just that. So as it is, the Ram was able to overcome just about all that and then some.

And yes, if the Ram did have AT tires on it, they would definitely reduce gas mileage as compared to SSA Goodyear tires. But, schmucks will be schmucks!



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