We used a Silverado 2500HD Crew Cab 4WD hitched to a 9,000 pound ballasted
trailer with a windscreen for the first run.
with the 6.0-liter gasser, we pulled onto I8 for an uphill climb against
a 2007 Dodge Ram Quad Cab 2500 powered by a HEMI 5.7-liter V8, rated at
345 horsepower and 375 lb-feet, and a 2007 Ford F-250 Super Duty Super
Cab with a Triton V10, rated at 362-horsepower and 457 lb-feet.
Ram and Super Duty were pulling identical 9K trailers with windscreens.
up against the Dodge and the Ford separately on the highway. When the
trucks were even with each other at around 45 mph, the drivers signaled
to each other to hit the gas and pound up the grade.
was quickly dropped but against the stronger V10 things got interesting.
The Super Duty initially pulled away from the Silverado HD from 45 to
about 52 mph, but from 52 to 70 mph the GM pulled up to and passed the
Ford, and from 70 to 75 both trucks stayed the same distance apart from
each other until both drivers took lifted the accelerator pedals off the
floor. We’re chalking this up to the Chevy’s 6-speed transmission
versus the Ford’s 5-speed. Both trucks were sporting 3.73 rear axles.
The second run up and down the hill was with the diesels. The Duramax
cab configuration was the same as the gas pickup, but this time towing
weight was bumped up to 12,000 lbs without a windscreen.
GM wasn’t able to obtain a 2008
Ford Super Duty with the new 6.4-liter 350 horsepower, 650 lb-feet
Power Stroke. These trucks just went on sale last week. A 2007 6.0-liter
PSD hitting 325 horsepower and 570 lb-feet was the only Ford diesel available.
Yes, the Chevy beat the Ford up the hill.
The Dodge also suffered similarly to the Ford. The Ram we drove ran with
the smaller 5.9-liter Cummins I6, which has been replaced for 2007 with
the larger 6.7-liter turbo-diesel that hammers out 350 horsepower and
650 lb-feet of torque. Yes, the Chevy beat the Dodge up the hill.
have to revisit this with another diesel
shootout at some point in the near future.
the other diesel products on hand, let’s get back to the Duramax/Allison
combo. For trailering, the Silverado has increased smarts in tow-haul
mode to help engine brake the truck during descents at load. This was
a spooky system before and it’s even spookier now at anticipating
the point at where you’d want to downshift and then doing it for
Add in Allison's
"tap shift" on the gear stalk, to manually shift the automatic
transmission, plus the integrated trailer brake controller that works
with the truck’s ABS system and trailers equipped with electronic-controlled
brakes, and you’re talking fine tuning options for hauling trailers
that allow the driver to so precisely control the rate of descent that
the smell of burnt brakes and risk of manual misshift has almost become
a thing of the past.
Heavy Duty with tow haul, tap shift, and integrated trailer brake control
is absolutely a professional’s tool.
By the time
you read this story, regular and extended cab GMT 900 heavy dutys have
already been shipping to dealerships.
wheel crew cab production starts on February 19th in Flint, Michigan and
Dually production starts April 19.
And as the
2007 GMC Sierra and Chevrolet Sierra Heavy Dutys ramp up production levels,
to make up 30% of all GM full size pickup sales, the engineering team
is heading back to work next week.
2010 is just around the corner and that means another round of major
changes to the Duramax to meet EPA requirements. Ford is hard at work
on this challenge and Dodge says they can already meet it.
We can hear
the treadmill clicking up another notch.