2015 Light-Duty V-8 Challenge: Braking

Ram 14

The best stopper of the group empty or loaded was the Chevrolet Silverado 1500, wearing 275/55R20 Goodyear Wrangler SR-A tires. When the Chevy was empty it stopped in 133.7 feet, and then stopped 1.5 feet better than that with 1,240 pounds of rock salt bags in the bed. Stopping better with a full load is not unprecedented, and it makes sense, given you have more weight over the rear axle and rear tires. Our test driver, Cars.com's Joe Bruzek, noted that the Silverado stopped hard, throwing him into the seat belt with a surprising amount of force.

2015LD_BrakingEmpty_F2

The empty GMC Sierra 1500 took about 5 feet longer to stop than the Silverado and it took more than 16 feet longer to stop with the salt bags in the bed. In fact, when fully loaded, the GMC groaned and lurched to a stop with a good amount of pedal vibration as the antilock braking system hunted for tire traction. The Goodyear Eagle LS-2 275/55R20 tires seemed to struggle for grip where the Silverado felt like it had dropped an anchor.

2015LD_BrakingLoaded_F2

The pickup with the best braking feel — empty and loaded — turned out to be the Ford F-150 with its newly designed (and quite wide) Goodyear Wrangler Fortitude HT 275/65R18 tires. When empty the Ford stopped in 139.9 feet and then 143.7 feet loaded. But what impressed Bruzek most was how confidently and composed the truck stayed during each test.

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The truck with the worst pedal feel was the fourth-place-finishing (in this test) Ram 1500, with its 275/60R20 Goodyear Wrangler SR-A tires (almost identical to top-finishing Silverado 1500). The empty Ram came to a stop in 143.7 feet, but loaded it took almost 20 feet longer at 161.6 feet. We should note that the 1,240 pounds we had in the bed plus the weight of the 175-pound driver was over our calculated payload for the truck by more than 250 pounds.

And in our final spot of the brake test, the Toyota Tundra TRD Pro — with its bigger, off-road-oriented wheel-and-tire combination and softer spring rates — stopped in 159.6 feet when empty, and did just a touch better with some extra weight on the rear end, stopping in 157.8 feet loaded.

Looking at the stopping power of each truck in another way, if you combine both the best empty and loaded numbers, you find the Chevy's total stopping distance at 265.9 feet, Ford's at 283.6, GMC's at 287.6, Ram's at 305.3 and Toyota's at 317.4.

How We Conducted the Testing

We conducted our brake testing on the same Wild Horse Pass Motorsports Park quarter-mile track where we ran our zero-to-60-mph and quarter-mile acceleration tests; however, for this test we chose a nice, even stretch of blacktop at the far end of the track. This surface allowed us to use the most consistent pavement the track offered, resulting in more repeatable stops.

Temperatures for the brake testing were in the low 70s; there was very little wind and high-level cloud cover. We made sure to run each truck above 60 mph to get into the transmission's top gear. Using our RaceLogic display, we were able to dynamite the brakes at the exact moment we hit 60 mph.

For our loaded runs, we used the same 31 bags of rock salt we used for zero-to-60 and quarter-mile acceleration testing; however, we had to do some load shifting to make sure the majority of the load was between the back of the bed and over the rear axle so we didn't have a moving tidal wave of rock salt plowing through the cab wall.

Cars.com photos by Evan Sears

Chevy 7

 

 

 

Overview | Acceleration | Quarter-Mile | Braking | Fuel Economy | Davis Dam | Results

Comments

The Ram in the picture shows a lot of nose dive. Isn't air ride supposed to limit that sort of thing?
The Chevy pictured showed less nose dive even though it had the most aggressive brakes.

The comment about Ford's quite wide tires makes no sense since all of the tires were 275's.

The difference between the GM siblings shows that brake testing should be done with all of the trucks on the SAME tires.

If by adding weight improves stopping distances per the writer The question I have is why did this only happen on 2 trucks? Am I missing something?

I am missing RAM braking video. Why ?

@Lou, Ram's air ride suspension is not an active suspension in the respect that it does not instantaneously adjust for brake dive, acceleration squat, or body roll.

"The difference between the GM siblings shows that brake testing should be done with all of the trucks on the SAME tires."

But you can't buy them all with the same tires...so think of it as showing you that, "Hey! I now know which tires perform better under braking!" instead of being the half full cup guy :-/

Shortest wheelbase, and softest spring is why the Ram exhibits the greatest pitch change.

So the only technical difference between the GM twins in braking was the tires? I mean, they have identical pads and rotors right? Does the GMC have different ABS programming?



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