[3/4-Ton 7% Grade]
[1-Ton 7% Grade]
[Diesel v Gas Comparison
[3/4-Ton 15% Grade] [1-Ton
15% Grade] [Diesel v Gas
Comparison 15% Grade]
All Grades] [Summary]
Gas Pickups - 7% Grade With 10,500# Trailer:
the hill climbs at Ford's Michigan Proving Grounds picture a single,
very large hill cross-sected at different angles by six two-lane concrete
paved roads, with gradients ranging from 7% to
60% (yikes!) and lengths stretching from 60-feet to 2,000-feet.
7% test distance was 1,476-feet long, or 450-meters according
to our British-sourced Oxford
Technical Solutions RT3102 monitoring unit. That's 156-feet more than
a quarter-mile, or 1,320-feet. Distance is shown in both feet and
meters in the graphs that accompany this part of the testing.
all the runs on the grades at MPG, both truck and trailer were completely
on the grade and stationary prior to the start of the run. All the
tests were performed 'brake-to-accelerator', i.e., foot brake fully
depressed with right foot, then lift and fully depress the accelerator
pedal in one movement with the same foot. Sufficient
distance was provided at the end to slow the rigs down to a safe speed
prior to the top of the hill.
minimum of three runs were carried out in each configuration tested at
wide open throttle (WOT), with the fastest run for each truck used
in the results.
to space and readability considerations, the bar graphs
below only show the test results from 200-m (656-feet) to 450-m (1476-feet).
See the summary table at the bottom for full test results from 50-m
times and speeds measured are shown cumulative over the run.
the graphs below: the lower a truck's bar is, relative to the other
two trucks' bars, in the "Time Over 450-Meters" graph the better it
performed. The higher a truck's bar is, relative to the other two trucks'
bars, in the "Speed over 450-Meters" graph, the better it performed.
shortest time required to cover the 450-meter distance determined the
best performing truck.
Gas Pickups 7% Grade With Trailer Summary
Dodge Ram 2500 Quad Cab 5.7-L V8 4x4 SRW 5-speed auto 3.73
Ford F-250 Super Duty Crew Cab 6.8-L V10 4x4 SRW 5-speed auto
GMC Sierra 2500 Crew Cab 6.0-L V8 4x4 SRW 6-speed auto 3.73
|50-m / 164-ft
|100-m / 328-ft
|200-m / 656-ft
|300-m / 984-ft
|400-m / 1312-ft
|450-m / 1476-ft
Gas Pickups 7% Grade Assessment:
a difference adding some gravity made to the contest for the gas pickups.
When you look at the performance numbers and truck specs, there's some
high drama happening among these haulers in the uphill quarter-mile.
Ford F-250 took full advantage of its Triton V10's stronger, earlier
torque peak to sprint off the starting line well ahead of the GMC and
Dodge - reaching 50-meters (164-feet) more than half a second before
the Sierra and almost a full second ahead of the Ram. The Sierra's gap
would probably have been wider if not for its 6-speed 6L90 HD transmission's
fast 4.03 first gear, a good foil to the Ford's 4.30 final drive ratio.
By 100-meters, even though the Ford still had the lead, both the Sierra
and the F-250 were traveling at identical speeds. But as both trucks
shifted into third and their transmission gearing became closer to
each other (1.55 in the Ford to 1.53 in the GMC) the massive and early
torque peak once again proved decisive for the F-250, allowing it to
build a bigger lead again at the 200-m mark. The Ford kept an edge
on speed until 400-m, when the Sierra finally started moving faster
than the F-250. But it was too late for this test's distance. The Ford
took the race by almost a full second over the GMC, and by more than
two seconds over the Ram.
the distance would have been longer, it's possible the GMC could eventually
have caught the Ford - which would have been similar to what we
the first drive of the 2007 GM Heavy Duty Pickups. This time, though,
brute force triumphed cog-swapping finesse.
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