HD Chevy 2500 LTZ, Duramax and 6-speed Allison
Auto, Hard to Beat
2011 crew cab, it has it all for a HD truck.
All the toys, if you're not use to the
ride of a HD, you might think it harsh. Yes compared to a Cadillac but
for HD pickups, it's a nice ride. Center console is more accessible as
it slants out for easy reach of controls. Buttons for volume under the
steering wheel, remote start, starts instantly, so quiet, you think it's
a car. Exhaust brake is great and works seamlessly with the Allison
auto, but the light on the switch is hard to see if it's on.
Now for 2011, GM went
massive truck improvement, as in frame, suspension, payload and towing
ability puts Chevy and GMC HD trucks at the top of their segment. It's
improvements we all want and of course the power and fuel mileage have
also improved. The new suspension keeps the power under control and
tires planted on the pavement. The new exhaust brake adds stopping power
to grade shifting from the Allison tranny and larger brake rotors this
New steering box, ratio's
and linkage add up to tighter steering changes and the new hydraulic
body mounts on the C-pillar, improved the crew cab ride. It's a truck
that takes the work out of all day towing on what's left of our
Interstate highways and finally a 36 gallon fuel tank to find the
cheaper fuel at the next town.
(LML 397 hp, 765 torque) diesel. The Allison grade shifting and the new
exhaust brake kept my foot off the brake. The exhaust brake closes the
vanes on the turbine side of the turbo to create back pressure. It's
fully integrated with the Allison 1000 6-speed automatic transmission.
The exhaust brake has an on/off switch with four operational modes:
tow/haul mode engaged, tow/haul mode disengaged, cruise control on and
cruise control off. So you can toggle down gears by switching from auto
to manual with the cruise on, it's just too easy.
new GM steering was smooth and easy, I could see the trailer brake
controller gain in the instrument cluster close to the gauges I watch.
Using tow haul mode with a trailer, down shifts are early to hold for
more braking, holding range longer so less gear hunting which is fully
integrated with the exhaust brake.
And they get better when
loaded, 14" rotors, almost the same size front and back with more than
an one inch increase, and proportional brakes that can change pressure
front to back where the most brakes are needed with a load. I remember
on the farm driving mostly on dirt roads. That gravel ate my trailer
brake magnets, so I knew my trailer brakes wouldn't always work, duals
helped but GM can balance brake pressure to help with the tongue weight
of a trailer pushing on the wrong end for max braking. The hydroboost
brake booster calibration takes less pedal effort.
2011 GM SRW trucks have
trailer sway control with integrated trailer brake control, to brake the
sway out of a conventional trailer if the problem arises. A big deal for
trailer safety. With hill start assist, the truck and trailer brakes
hold a couple seconds while you go from brake pedal to gas pedal. The
revised Allison auto has automatic grade braking, intelligent brake
assist and exhaust brake on the Duramax diesel. Towing trailers is
getting safer and easier.
New asymmetrical design is
from unequal front and rear spring half lengths, which minimize axle hop
and enhance traction control efficiency better than anything I've had on
pavement. StabiliTrak electronic stability control system on all
single-rear-wheel models greatly improves an empty trucks handling on
slick roads. 2500HD models feature a two-stage leaf-spring design, while
3500HD models have a three-stage design. All models feature 3-inch-wide
leaf springs that are 20-percent wider than previous models.
The larger leaf-spring
design supports increased rear gross axle weight ratings across the
board. On the 2500HD models, the rating is 6,200 pounds, up from 6,084.
On 3500HD models, the rating increases to 7,050 pounds on
single-rear-wheel models and 9,375 pounds on dual-rear-wheel models, the
latter representing a nearly 14-percent increase over the previous
GM 3500 duallys can tow up to 21,700 lb gooseneck/5th wheel trailers
with a 6635 lb payload. GCWR is 29,200 lbs, 17,000 lb conventional
trailer without weight distributing. That's impressive, SRW (single rear
wheel) trucks are rated at 13,000 lbs conventional trailer without WDH
(weight distributing hitch) and DRW (dual rear wheel) trucks are rated
at 17,000 lb without WDH.
The independent front
suspension has forged steel upper control arms, cast iron lower arms
with bigger shock towers and a pair of urethane jounce bumpers on each
side, instead of one. Torsion bars and torsion bar attachment frame is
larger and adjustable. 5 different torsion arms rating instead of one.
The trim height is adjusted on each bar via a single bolt, easily
allowing the height to be changed to account for the weight of a snow
plow or other accessories
new emissions diesel uses urea (DEF) which basically costs what it saves
in improved MPG (2% diesel
exhaust fluid or urea). The
tank is outside the frame under the passenger side of the cab, picture
left. It holds 5.3 gallons with a range close to an oil change 5, 000 to
8,000 miles. The fill cab is under the hood (picture left,) easier for
filling with gallon jugs.
after-treatment have been optimized to provide about 700 miles between
diesel particulate filter regenerations, a 75-percent improvement over
the previous system and significant contributor to improved fuel
efficiency, as the regeneration process requires extra fuel.
Improvements to the new
Allison 1000 6-speed auto include torque converter with a new two sided
lockup clutch, twice as much as before to handle the extra power from
the LML Duramax. A new stator for torque multiplication new valve body,
modified clutches, stiffened case for drive train power and larger
output shaft on 4x4's. Fifty-seven new parts, made for the extra diesel
power and new integrated exhaust brake.
Chevrolet 2011 Silverado 2500 4WD LTZ Crew Cab 10,000 lb
GVW as reviewed.
Off Road Suspension Package:
Off Road Skid Plates
LTZ Plus Package:
Locking Tailgate, EZ Lift Tailgate,
Universal Home Remote, Rear Wheel house liner, Adjustable pedals and
rear park assist
Duramax 6.6L V8 Turbo Diesel:
Allison -Speed Automatic Trans: $1200
20 in Forged Alum Wheels $850
Rear Vision Camera System
Head Curtain Front air bags
Mirrors, Camper Style, Heated
Changes for 2012 HD
enhanced fifth-wheel towing, engineers strengthened the pickup box sills
and other box structures, rear springs, u-bolts and box mounts, and
upgraded the shock tuning. As a result, GM 3500HD now has a
best-in-class tow rating of 23,000 pounds, up from 21,700 pounds in
GM also will lead the class in
dually payload, with a 7,215-lb. payload for the 3500HD regular cab
gasoline dually. Updates to the trailer hitch receiver increase
conventional towing to 18,000 pounds, up from 17,000 pounds. Both
changes will be on models arriving in dealerships in the fourth quarter.
2012 GM 3500HD
2012 Ford F-350
2012 Ram 3500
fifth-wheel towing (lb./kg):
conventional towing (lb./kg):
payload capacity (lb./kg)
Other updates for 2012 Sierra HD trucks
include a new navigation radio with enhanced display and a hard drive,
eliminating the need for discs with map data.
Sierra continues to offer OnStar, a
segment exclusive, SiriusXM satellite radio, Bluetooth for phone and USB
leads the class in payload, with a 7,215-lb.
capacity. Chevrolet offers 10
2500HD models and eight single- and dual-rear-wheel
3500HD models, including regular cab, extended cab
and crew-cab body styles offered in 2WD and 4WD. All
share key architectural and performance features,
- Available 6.6L
Duramax diesel delivers 397 horsepower and 765
pound-feet of torque and B20 biodiesel
- 36-gallon fuel
tank and engine efficiency to enable up to 680
miles between fill-ups with the 6.6L
Duramax turbo diesel
- Smart exhaust
brake feature provides greater control on grades
and reduced brake pad wear
- An array of
standard and available control features,
including trailer sway control, integrated
trailer brake control, hill start assist,
automatic grade braking, intelligent brake
assist, and large brakes.
For 2012, Silverado
HD offers a number of technical features that
enhance the capability of the truck for both work
and recreation, including a new navigation radio. It
offers an enhanced display and now has a hard drive
that eliminates the need for discs with map data.
Silverado also continues to offer segment exclusive
OnStar Directions & Connections with Turn-by-Turn
Navigation and Automatic Crash Response, SiriusXM
satellite radio, Bluetooth for phone and USB
powered by Autonet, available through Chevy dealers,
turns the Silverado HD into a mobile hot spot and an
office on wheels, providing multiple users with full
internet access inside the vehicle or up to 150 feet
from the exterior of the vehicle.
For work sites, Chevy
WiFi offers instant access to online ordering sites,
municipal sites with building permits and building
code information and more. For families on the go,
passengers can connect with friends on social media
sites, stream videos, find maps, check weather or
search for fishing and camping sites.
Silverado HD also
offers comprehensive confidence and control
features. Trailer Sway Control, which uses the truck
and trailer brakes and the powertrain controls to
keep the vehicle and trailer on the intended path,
is now part of StabiliTrak, as is Hill Start Assist,
which avoids roll-back before accelerating on
New Z71 Appearance
Even trucks that work
for a living should look good while doing it, so for
2012 Silverado HD will offer a HD Z71 appearance
package for LT and LTZ models that includes a
body-colored grille surround with a chrome mesh
grille, body-colored bumpers and lower fascia,
18-inch polished forged aluminum wheels and other