In the second favorable trend, an effort is being made to reduce the weight
of unladen trucks. A weight cut may help a truck meet a low bridge capacity
limit or comply with a difficult gross weight limit.
Mack has said that, under certain conditions, its trucks can go 30,000 miles
or 700 hours running time, between oil changes. Mack also is increasing
transmission and rear-axle drain intervals to 210,000 miles or two years
for standard-drain lubricants and 420,000 miles or three years for extended-drain
lubes.
Eaton Corp. has announced that some of its transmissions and drive axles
can now go up to 500,000 miles between lubricant changes . Eaton also is
expanding use of low-maintenance wheel ends for steer and drive axles while
adding a low maintenance brake system package. The company said it was the
first North American drivetrain supplier to advocate use of synthetic lubes
in its products, and is the first to approve a 500,000-mile drain interval
for both its transmission and drive-axle products.
Spicer Clutch Division of Dana Corp. is promoting its Solo clutch as being
maintenance free . "The Spicer Solo Clutch was introduced last year
as the first adjustment-free clutch for medium-duty trucks and the feedback
has been tremendous," said Kevin Schlosser, Spicer Clutch chief engineer.
"The technology has been proven to save money by decreasing labor time
and increasing the life of the clutch; and now these benefits are available
for heavy-duty trucks, as well."
Spicer also has replaced its popular 10 Series driveshaft assembly with
completely re-engineered driveshaft assemblies for the next century's truck.
Meanwhile, Rockwell's brake operation has reported that its Q Plus cam brakes
can go lubrication-free for 500,000 miles or three years . In addition,
Rockwell said its advanced lube program for reducing lubrication services,
introduced in 1992, is living up to its potential of saving $42,200 and
5,000 gal of lubricants per 100-unit fleet over one million miles of vehicle
operation.
Curbing the time a truck must be off the job for maintenance work sounds
attractive but this warning bears repeating-heed the fine print, and that
applies to all the details.
Some lengthy service interval plans require the use of synthetic lubricants.
Others forbid their use. Recent introductions of semi-synthetics make things
more complicated. It's up to the operator to know and follow the rules.
Violating them can void the warranty on a component or on the entire vehicle.
The rules can be quite extensive. Among other things, the changes in drain
intervals on Macks call for use of the Mack Centri-Max oil filtration system
and use of genuine Mack replacement parts. Only selected E-OL oils can be
used. A Mack dealership has the information on which oils qualify.
The list of long-life parts and supplies is growing steadily. No one producer
clearly has the lead as tires with the radial ply design join maintenance-free
batteries in a growing number of trucks. General Motors appears to have
an edge in some changes, such as a move to long-life engine coolants.
Advanced electronics are playing major roles in developments ranging from
longer intervals between tune-ups for trucks with gasoline engines to replacing
mechanical controls in managing today's diesel engine.
When it comes to putting trucks on a diet, Kenworth and Navistar have scored
notable advances in the industry-wide effort to enhance productivity by
reducing unladen weight. Advanced air suspensions, in which rubber air springs
are used in place of the metal springs seen in conventional suspensions,
are enjoying a sales boom because they deliver an improved ride to truck,
driver and cargo while reducing truck weight.
The Kenworth line has just unveiled its Airglide 200 air suspension, which
the producer said is more than 400 lb lighter than the older Airglide 100
model . The new offering has a rating of 40,000 lb. "In addition to
road and track testing, our lab features computerized samples of some of
the worst roads in North America," commented Tom Moran, project engineer
on the Airglide 200 work. "We did a series of durability and performance
tests and we even built a special suspension simulator. The Airglide 200
was tested way beyond what would be encountered in everyday driving."
With a weight of less than 12,500 lb, the International 9200 Ultra-Lite
is the lightweight leader from Navistar . The producer said it is up to
1,500 lbs lighter than competitive Class 8 daycab models, which have no
sleeper compartment.
Wide use of aluminum components, Super Single tires-rather than duals-at the rear; a Caterpillar 3176 engine, 10-speed SpicerLite transmission and International Air Ride suspension are key specifications of the light truck. "The International 9200 Ultra-Lite tractor is part of an ongoing lowest cost ownership effort to develop products that help improve the truck customer's bottom line," said Michael Cancelliere, director of heavy truck marketing for Navistar. "These new trucks are lighter in weight without sacrificing strength or durability."
