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It’s a wide-sweeping
change, and the effects are still being felt throughout the industry.
October 1, 2002, was the deadline for on-highway truck engine manufacturers
to comply with new federal regulations for exhaust emissions. On
that date, the United States Environmental Protection Agency (EPA)
required diesel engine manufacturers to restrict nitrogen oxides
(NOx) to 2.5 grams per brake-horsepower-hour and to cut particulate
emissions to 0.1 gram per brake-horsepower-hour. It’s a tough
rule.
Cummins was the first
manufacturer to launch a diesel truck engine that complied with
the new rule, and most other engine manufacturers also have followed
suit. Cummins markets two engines—the 15-lit. ISX and the 10.8-lit.
ISM—that use a technology called cooled exhaust gas recirculation
(C-EGR) to meet the regulations. Horsepower ratings on the ISX range
from 385 to 565; the ISM ranges from 280 to 370 hp. And through
a program of “Banking and Trading” exhaust emissions,
Cummins can market its 8.9-lit. ISL and 8.3-lit. ISC engines as
EPA-compliant. Another smaller Cummins engine has emissions well
below the EPA standard, and Cummins can trade those reductions for
a higher level of emissions in the ISL and ISC engines. Horsepower
ratings on the ISL range from 310 to 335; the ISC ranges from 240
to 330 hp.
“We run the engine
through a test cycle, and we have to demonstrate that we can meet
the standard,” states Roe East, director of product management
at Cummins. “I think cooled EGR is very effective at reducing
NOx. With EGR, we take exhaust gas out of the exhaust stream, cool
it, and put it into the intake side of the engine. As that gas mixes
with the air and fuel, it inhibits the combustion process somewhat.
You get a lower flame temperature and lower NOx levels. It is a
very proven technology and has been used for years on engines. There
are more than 12,000 Cummins engines with cooled EGR in real-world
service today, and they have accumulated over 270 million miles
of experience.”
Progress at Caterpillar
Caterpillar’s diesel engine builders have chosen a different
path. Rather than use C-EGR technology or some variation of it,
Caterpillar has developed ACERT, which stands for advanced combustion
emissions reduction technology. Caterpillar did not meet EPA’s
October 2002 deadline with ACERT, and as a result, the company is
paying fines for noncompliant engines.
In the meantime, Caterpillar
is selling so-called “bridge engines” that bridge the
gap between older engines and those with ACERT systems. The bridge
engines, which use oxidation catalyst technology, became available
in October 2002. They are the 3126E, at 190–330 hp; the C10,
at 305–335 hp; the C12, at 335–430 hp; and the C15, at
435–525 hp.
With ACERT, the C10 and
C12 have become the C11 and C13 engines. The C13 and C15 engines
became available this October with ACERT, and the C11 will be available
in December 2003. In addition, a C9 engine, with 275–400 hp,
may be well suited for some construction applications. According
to Caterpillar, by January 2005, all of its engines sold for construction
trucks will have ACERT systems.
Recently, Caterpillar
announced the availability of its C18 engine with ACERT technology.
The C18 is an 18.1-lit. off-road engine with five ratings from 575
hp to 765 hp. Cylinder heads on the C18 feature cross-flow design
and four valves per cylinder. The company claims that this design
provides better distribution of air throughout the combustion chamber.
In turn, that makes combustion more complete and emissions are reduced.
The C18 also uses the Cat electronic fuel injection system, which
has millions of hours of proven experience.
Highlights of the
Latest On-/Off-Road Truck Technology
Mack recently introduced its Granite series of construction trucks,
which will replace the popular RD series. Mack has built the RD
series for 38 years and has announced that the last RD truck will
be made December 1, 2003.
The Granite has a galvanized
steel cab but is designed to be an exceptionally lightweight vocational
truck without sacrificing durability. A number of Granite components
are aluminum, including the front bumper, the grille surround, the
grille, and the fuel tanks.
The Granite is offered
in two models—the CV7 or the Granite Bridge Formula. Designed
primarily for southern California or Arizona, the bridge formula
has a trailing tag axle, an aluminum front motor support, and a
lightweight 20,000-lb. steering axle. You can get a Cummins 8.9-lit.
engine in the Bridge Formula—making it 400 lb. lighter than
with a Mack engine. “The Granite series allows customers to
spec weight-savings components to match their applications,”
points out Steve Ginter, Mack’s vocational product manager.
“The Granite has
a larger cab and much greater visibility—you can see 14 feet
in front of the bumper,” he continues. “It’s got
a new door design with larger window openings—you can see the
front left fender through the left window.”
Both Mack’s AMI
series of high-torque-rise engines and the AI series of Econodyne
engines are available in the Granite. The AMI engines have a 60%
torque rise and are available in 300-, 335-, and 370-hp models.
The AI series ranges from 300 to 460 hp.
Ginter states that Mack
meets EPA emission standards with internal EGR systems. The introduction
of exhaust gases into the combustion chamber requires a delicate
balance. Bringing back more exhaust gases will reduce combustion
temperatures and NOx levels, but too much exhaust gas will increase
particulate emissions.
“We were able to
get the same horsepower and the same oil-change intervals and have
only a minimal impact on fuel economy with EGR systems,” Ginter
relates. He estimates that EGR increases fuel usage by 0–5%
on average.
At International Truck
and Engine Corporation, all construction trucks and trash haulers
are called “severe service.” That includes the 7000 series
and 5000 series trucks. All 7300, 7400, and 7500 trucks have International
engines. In the 7600 series, International offers Cat C10 or C12
engines with up to 430 peak hp or the Cummins ISM engine with up
to 385 peak hp.
“We will meet emission
requirements through cooled EGR systems by January 2004,” maintains
Bill Sixsmith, severe service marketing director at International.
“When the October 1 [2002] deadline came out, we were assessed
a small fine, and the government said we didn’t have to meet
the more stringent regulations until January ‘04.” He
says the company’s EGR systems require a larger-capacity radiator
and a new turbocharging system.
A major differentiator
for International’s 7000 series is its Diamond Logic electrical
system. Instead of cutting into chassis electrical systems to wire
the body’s electrical functions, International uses a remote
power module that body companies simply plug into. The system has
an electronic controller, uses just nine pairs of twisted wires
to handle all electrical functions, and can self-diagnose electrical
problems by indicating specific fault codes. Many truck problems
are electrical, and Sixsmith says this new system can greatly reduce
diagnostic time.
Freightliner offers an
extensive lineup of construction trucks. At the heavy end is the
FL 120SD (severe duty) with either a set-back front axle or a set-forward
front axle. The set-forward model has a 120-in. BBC (bumper to back-of-cab)
and can carry up to 1,500 lb. more than the set-back model. Engine
options on the set-forward model include Detroit Diesel, Cat, and
Cummins units up to 600 hp.
Both Freightliner and
Sterling trucks feature the TufTrac suspension, a severe-duty, six-rod
vocational system with the advantages of high articulation, good
weight equalization, and a good ride. TufTrac combines taper-leaf
springs and a rubber elastomer center pivot to achieve good articulation
and requires no lubrication or regular maintenance. (Sterling trucks
have their origin as Ford’s heavy-duty line, which Freightliner
bought. See more below.)
Freightliner’s Business
Class mediums begin with the FL 50 and FL 60 but can handle larger
jobs with the FL 70 medium and the FL 80. The FL 70 comes with horsepower
ratings up to 300 and gross combination weights up to 50,000 lb.
On the FL 80, gross vehicle weight ratings range up to 64,000 lb.;
again, its horsepower ranges up to 300.
The FLD 112SD has a set-back
front axle and a short, 112-in. BBC. The 112SD can fit engines up
to 400 hp and is available from Cat, Cummins, or Detroit Diesel.
All-wheel drive is offered as well.
Peterbilt’s main
construction vehicle is the Model 357, which is available as a truck
or a tractor but mainly is sold as a truck. If you want a construction
tractor from Peterbilt, you probably want a Model 379 or 378, which
specs out lighter and can achieve higher payload weights.
“The 357 has a new
set-back hood and front axle,” describes Ray Paradis, director
of vocational markets for Peterbilt Motors. “The deeper slope
to the hood provides better visibility.” The 357 comes in three
hood lengths and two front-axle positions. Cat and Cummins engines
are available up to 475 hp.
The 357 has an all-aluminum
cab, and Peterbilt claims it is the lightest-weight truck in the
industry. “You can spec the truck with a number of aluminum
features to give you a lightweight truck or tractor, which equates
to higher payloads,” notes Paradis. He maintains that the construction
business is very important to Peterbilt and has helped support sales
in the last year.
Sterling Truck Corporation
recently announced the availability of the Dana Spicer Central Tire
Inflation (CTI) System for L-line vehicles. Truck operators can
easily change tire pressures while in motion, allowing trucks to
meet the demands of off-road use and soft terrain. CTI operates
by using the vehicle’s onboard air compressor. Steer-and-drive
tire pressures are microprocessor-controlled to maximize their tractive
effort. Operators can choose from three pressure modes: highway,
for high-speed travel on paved surfaces; off-highway, for easy operation
on unpaved surfaces; and emergency, which is extra-low pressure
to help free a stuck vehicle or to handle other extreme conditions.
Sterling’s L-line
offers four BBCs: 101, 111, 113, and 122 in. Engines, up to 600
hp, come from Cat, Cummins, Detroit Diesel, and Mercedes Benz. Both
manual and automatic transmissions are available. Front axles reach
22,000 lb., and rear axles go up to 52,000-lb. capacity.
For its Acterra medium-duty
and vocational truck, Sterling recently introduced a factory-authorized
all-wheel-drive conversion. The feature is manufactured by Fabco
Automotive Corporation and now will fit all Acterra 4x2 versions;
conversions for Acterra 6x4 trucks are expected later this year.
The conversion is offered with front-axle ratings of 12,000, 14,000,
or 16,000 lb. and comes with a choice of one- or two-speed transfer
cases.
Volvo’s primary
construction truck is the VHD, which can be spec’d as a truck
or a tractor. The tractor comes standard with a 113.6-in. BBC and
a Volvo D12 engine boasting 365 hp.
To meet EPA’s October
2002 emissions standard, Volvo uses an EGR system with V-Pulse technology.
The system does not require a variable geometry turbocharger to
achieve the EGR necessary to reduce combustion emissions. Volvo
reports that V-Pulse technology achieves EGR “by harnessing
naturally occurring engine pressure as a means to reintroduce up
to 30% of the combustion by-product back into the intake mixing
chamber.”
According to the company,
Volvo’s 2003 VHD 200 model features an automotive-inspired
interior for maximum driver comfort and safety. To minimize stress
and fatigue, the interior features a wrap-around dash, and gauges
and switches are within easy view or reach. A primary display computer
limits what systems the driver can operate while the vehicle is
in motion, thus ensuring that attention is directed to driving.
Other key features of the VHD 200 are a single-rail frame, which
is lighter than a double frame. In addition, the truck has clear
space in back of the cab and on top of the frame to simplify body
installation.
Kenworth’s mainstream
construction truck is the T800, which has a set-back front axle
and is offered with two BBCs: 112 and 121 in. “The set-back
axle makes it easy to load up the front axle and gives it a good
turn angle,” remarks Mark Hampson, a senior applications engineer
at Kenworth Truck Company. As with Peterbilt, Kenworth is a division
of PACCAR Inc. The T800 can accommodate any one of three Cat engines
up to 525 hp or either of two Cummins engines to 565 hp.
Front axles from 12,000-
to 22,000-lb. ratings are available on the T800, and rear axles
are offered from 21,000-lb. single to 70,000-lb. tridems. Kenworth
markets seven frame-rail sizes to match strength and weight requirements.
A sloped hood for better visibility is standard, but you can spec
an optional straight hood for a traditional look.
Another Kenworth vocational
truck is the W900, which can accommodate up to a 600-hp engine.
The truck has a long hood and cathedral grille and comes with either
a 121-in. or 130-in. BBC. Rear axles range up to 52,000-lb. tandems.
Western Star, which is owned by Freightliner, features an extensive
lineup of construction trucks, including the following:
- The 4900 EX, which
has a 132-in. BBC and up to 58,000-lb. rear-axle capacity
- The 4900 SA, with
two BBCs—109 and 123 in.—and up to 58,000-lb. rear-axle
capacity
- The 4900 FA, with
two BBCs—109 and 123 in.—and up to 52,000-lb. rear-axle
capacity
- The 4900 EX dump
truck, with a 132-in. BBC and engines from two manufacturers
- The 4900 FA dump
truck, which can be spec’d with rear axles up to 58,000 lb.
All trucks can be spec’d
with any of a full range of manual, automated, and automatic transmissions.
And all of the above trucks can take engines up to 600 hp. Western
Star is a popular nameplate among dump truckers and freight haulers
in the Midwest and Northeast US.
Frequent contributor
Daniel C. Brown is the owner of TechniComm, a communications business
based in Des Plaines, IL.
GEC
- November/December 2003
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