If fleet managers could predict the future, the first question they'd ask would probably be: "What's the forecast for tomorrow's truck?" This information would help to prepare specs for their next chassis and component purchases.
Since no such crystal ball exists, many haulers and recyclers - in-cluding those from large fleets, municipalities and small independents - have been involved in the Tomorrow's Trucks program, organized by the Society of Automotive Engineers' (SAE). The program o-pens the lines of communication between the people who operate and maintain vehicles and those who engineer and design them.
Engines Although improvements have been made in engines, several hurdles still must be overcome. Aerodynam-ics have reduced the frontal area of trucks, resulting in smaller radiators and charge air coolers (CAC). In the meantime, emission regs have resulted in increased temperatures and pressure on these units.
The truck and engine original equipment manufactures (OEM) must define their goals to ad-dress these problems. Engine OEMs have set certain performance requirements for CACs. However, the major CAC suppliers maintain that it's unrealistic to demand a 700,000-mile CAC life for a Class 8 truck, since cost-effective materials have difficulties withstanding the pressure and temperature ranges of today's en-gines.
Another engine issue is cold water leaks. Proper hose and clamp specs and frequent maintenance can prevent leaks, according to OE engineers. Fleets, however, hope to re-duce the amount of time a truck spends in the shop.
To that end, engine manufacturers are working to ensure correct fit; some are even eliminating hoses in favor of more permanent parts. Va-rious new casting processes help to eliminate parting marks, which in turn eliminates the grinding required to produce a semi-concentric end. Some manu- facturers believe using full-bead barbs and clamps that require no input from technicians (other than orientation) will eliminate cold water leaks and reduce cooling system maintenance hours.
Perhaps the greatest problem remaining, according to both fleet and OEM reps, is water pump failures, which generally are blamed on coolant quality. Coolant overdosing and low supplemental cooling additive (SCA) also cause water pump problems.
One solution seems to be long-life coolants. These organic acid cool-ants reportedly protected engines without SCAs during tests done at 278,000 and 335,000 miles. An extender package also is recommended to enhance SCA at 500,000 miles and to extend coolant usefulness to approximately 750,000 miles. This not only minimizes water pump leaks, but also requires less maintenance time to check SCA concentrations and results in less waste, less recycling, fewer overdosing mistakes and fewer solids.
For fan control, truck OEMs are beginning to use engine electronic control modules (ECM). However, ECMs might send a signal to another black box. Another barrier to ECM use is determining which operating parameters actually turn on the fan. These could include the coolant, a rise in coolant temperature, the air inlet temperature, the engine oil temperature or freon compressor demands.
Cabs And Controls Increasing visibility is a top priority for fleet managers and OEMs alike. Although improved mirror technology has helped enhance visibility in new vehicles, defogging systems still are inadequate, according to fleet managers. They also complain of insufficient air volume in the windshield area.
For their part, OEMs are paying increased attention to visibility, es-pecially hood configuration. The technology exists today - through video equipment and proximity sensors - for 360-degree driver visibility. Specing this equipment ultimately comes down to cost versus value, according to the OEM rep.
Major factors in driver comfort and retention include seating, heating and air conditioning, noise and vi-brations. While great strides have been made in air conditioning, more than half the drivers in a survey by The Maintenance Council (TMC) gave their seats failing marks. For driver comfort, some OEMs currently offer mechanical or inflatable lumbar support as well as side and bottom mechanical or inflatable booster adjustments.
Adjustable dampening via shock absorbers is an option for the future. Over the longterm, OEMs are considering electronically controlled shock absorber dampening adjustment. This technology sends an electrical current through the fluid, causing it to change viscosity and, therefore, adjust the seat dampening. This method allows for constant and instantaneous adjustment.
In addition, with fleets seeking a 10-year cab life, construction is a major concern. In a recent survey, fleets reported that the quality of cab construction has decreased over the past 12 years. Areas that received poor marks included door hardware, cab rusting and water problems such as leakage and moisture migration into non-visible areas. Closer tolerances, such as door fit, can control water problems. To inhibit paint erosion, external components can be attached with gaskets and mounted using stainless steel hardware.
Meanwhile, every OEM has demonstrated "a higher level of confidence by extending their cab warranty," concluded a manufacturers' rep. Today's average cab warranty is 60 months unlimited mileage, compared to 36 months a few years ago.
Finally, today's commercial vehicles are becoming more sophisticated electronically. Increasingly, computers and electronic controls are helping to solve performance, operational, safety and environmental problems. Simplified training, however, is important to retain drivers.
In addition, hand-held electronic tools are an area of concern for fleet managers. They want a standardized, universal diagnostic tool with a five-year life. In general, managers feel that tools are too expensive, don't provide sufficient diagnostic direction, may have inconsistent user interfaces and may not service all the desired equipment. Tool cartridges also must be changed far too frequently to keep up with the vehicle systems.
Meeting these requirements cost-effectively, however, is a formidable task, according to OEM reps. Be-cause tools are a low-volume business, costs must be spread over a much smaller customer base.
Adequate tooling also is key for effective fleet maintenance management. Fleet managers want manufacturers to design vehicles and components to use existing, standard tooling. Currently, managers are restricted by the lack of common tools to service equipment from different manufacturers. In addition, specialized tools can be expensive.
However, some hand-held tools are now available that only require inserting a specific card for each electronic engine. Future designs of on-dash display screens also will allow for common programs, thus reducing or eliminating the need for redundant equipment.
Chassis Reliable, durable, easy to repair and, most important, safe braking systems, including anti-lock braking systems (ABS), sum up the managers' main requests for the chassis. In response, manufacturers now offer reliable ABS as standard truck equipment.
Other braking systems, however, still are under hot dispute. For ex-ample, the S-cam foundations brake will remain dominant, according to an OEM rep, because it is "proven, simple, economical, robust and easy to repair." Fleet reps argued, however, that disc brakes have been the answer in the automotive industry. Likewise, they want a reliable, cost-competitive disc braking system for heavy-duty vehicles.
OEMs, however, believe the concept of cost-competitive disc brakes is an oxymoron. In a heavy truck, an air (not hydraulic) disc is the only practical method to apply enough input force to the foundation brake and still have a control system that can easily be coupled to a trailer. For reliability and performance, the power multiplying mechanism and the adjusting mechanism must be robust and have low drag. This is much more costly than closed hydraulic systems.
Other concerns for braking systems include compatibility, uniform apply and release timing, standard torque and pneumatic balance. Field tests demonstrate that aftermarket linings are the largest contributing factor in tractor and trailer imbalance. Establishing a rating system for aftermarket linings would help reduce imbalances from relining.
Finally, a real need exists for interactive suspensions that will increase driver comfort, reduce weight and increase durability. Currently, suspensions are "active" because they react to vibrations created by the road surface. "Interactive" suspensions, on the other hand, would process input from several sources, in-cluding the driver, and adjust ac- cordingly.
Perhaps the key to optimum suspension is to ask drivers their opinions on which height provides the best ride. They'll also know which height hinders performance due to factors such as pinion angle and tire-to-trailer undercarriage.
Trailers Currently, most fleets avoid powered landing gears due to high initial cost and maintenance requirements. However, excessive personal injuries have caused some to ask for more efficient landing gear, with 20 or less turns of a crank in low gear per inch of travel.
OEM reps noted that a compromise must be reached between ease of lift (and therefore less injury potential) and the number of crank turns required. Although a landing gear could be designed to meet fleets' request, it might not lift effectively and could hinder the operator's ability to crank under a heavy load. The best solution, according to the OEM rep, is to get the gear to the ground quickly in high gear. Then the driver should switch to low gear to lift the trailer from the fifth wheel - at the expense of a few extra turns of the crank.
Electrical Systems Electrical technology has advanced enormously. However, fleet reps were generally concerned with the limited use of high-quality components, even though it would re-duce warranty claims and improve customer satisfaction.
Long-life headlights are now standard with most OEMs and sealed beam halogen lights are available as an option. Although light-emitting diode (LED) technology has extended the life of marker and stop/tail/turn lights, their cost is still too high, ac-cording to fleet reps. Meanwhile, some manufacturers are considering using high-intensity discharge lights that save energy by producing more light per watt; these lights also last longer and run at a lower temperature than incandescents.
For other lights, manufacturers are working with suppliers to reduce water intrusion. Most lights now feature shock-mounted bulbs to reduce failures. Future lighting alternatives include neon and fiber optic devices.
Currently, most manufacturers provide convoluted tubing to protect harness wiring, according to the OEM rep. Some have improved their clips, cable ties and clamps, providing an increased number and taking care to route wires to avoid chaffing. However, in some areas of the harness, temperatures are higher due to low air flow; alleviating this problem requires careful insulation selection and, in some cases, special fluid compatibilities.
OEM reps also acknowledged that cable splices still are needed. To ad-dress this, one OEM heats tubing to protect the splice from water. For ap-plications exposed to splashes, another OEM specifies a dual-wall heat shrink with a meltable inner liner. Another development is using splice packets to improve the splice.
Finally, OEMs are developing new instrumentation clusters to standardize wire and circuit coding. Also, the amount of wiring is reduced when the SAE J1587 data link is used to drive the gauges. Some manufacturers are using bussed centers instead of individually wired systems for power distribution.
Another dilemma for fleet managers is increased replacement costs and vehicle downtime due to unitized dash systems. Fleet reps would prefer more easily diagnosable and field-repairable systems that don't require expensive, specialized tools. Also, odometers currently cannot be field-programmed by the fleet. For dash gauges and switches, fleet reps want quick, easy replacement; diagnostics also should be improved and fault-logging expanded.
A recent TMC survey indicated that headlamp connectors and start-er connections still pose the foremost problems for managers, despite the benefits of sealed connectors. Ground circuits also must be im-proved to accommodate low-voltage electronic components.
In response, many manufacturers have begun to use Packard connectors, sealed for exterior applications, and Deutsch connectors in select applications. These connectors require repair kits with the correct pins and tools for insertion.
Bulkhead connectors are preferred for service reasons, but their size has greatly increased due to the number of wires needed to run in and out of the cab. Current carrying capacity also is becoming a concern. The number of pins required and the density are increasing; to compensate, pin sizes are sometimes de-creasing. Currently, no truck chassis OEMs provide a standardized body connector for the body manufacturers.
For sensors, the trend is to use integral Packard-like connectors instead of ring terminals. Often this provides a two-wire sensor rather than a case-ground sensor; the two-wire sensors reportedly can interface more easily with the truck's electronics.
As these changes demonstrate, fleet managers are keeping manufacturers on their toes. Tomorrow's truck will be more efficient and user-friendly - but there will always be room for improvement.
How does a small, independent waste hauler compete in today's marketplace? Tulsa, Okla.-based American Waste Control has found its formula: * Find your niche and specialize.
* Provide unbeatable customer service.
* Seek and maintain the best em-ployees possible.
* Use computers to help manage your business.
Originally, owner Ken Burkett formed a residential collection operation. When the city took over his service area and set pricing, Burkett sold out and bought a bankrupt commercial waste service in 1980.
The new company's rolling stock included a rundown front loader and a roll-off. "We didn't even have a shop and had to do our maintenance outside," Burkett said.
"Facing large competitors [has helped to reveal] our own capabilities," he said. For example, he found that placing relatively small roll-off containers at construction sites can be profitable, particularly in locations with limited access.
While most haulers supply 30- and 42-cubic-yard containers, Burkett uses 16-yard roll-offs. These are popular with independent construction contractors and homeowners who are remodeling their houses. "That's when our little trucks make more money per dollar invested than any other vehicle in our fleet."
To help maintain equipment and for more efficient routing, American Waste Control uses personal computers. Burkett bought a RDS Refuse System from Reliable Data, Hunt Valley, Md., in 1983.
"With four trucks running, manual billing took three or four days. We now have 23 vehicles and it takes eight or nine hours for computerized billing," he said.
The system, which is upgraded every two years, tracks hundreds of roll-offs and thousands of front loader containers. It also helps watch for late payments and enforce late fees. Daily route sheets contain information such as customer addresses, the number of containers and a contact name, hours when the customer can be served and street access and safety information. Route productivity can be tracked as well, showing container types and cubic yards collected.
For trucks, Burkett stresses proper maintenance. He only uses high-quality motor oil and changes it every five weeks. Every truck is greased twice monthly.
American also does its own tire repairs and all major engine work, including transmission and clutch re-pairs. Pull-down reels provide convenient access to motor oils, hydraulic fluids, gear lube and grease.
But Burkett admits that maintenance is only part of equipment care. "You need careful drivers. Some of the best maintenance happens behind the wheel," he said.
Burkett has never sought to manage a big company. "I want to have personal contact with the drivers and customers," he said.
In addition to clear business strategies, American Waste Control has prospered through the hard work of its employees -- the mechanics, drivers, salespeople and office staff.
"They are like eagles," Burkett said. "They don't flock; you find them one at a time."