Auto Service World
Feature   May 1, 2007   by John G. Smith

Long-Haul Repair Trends

Reports from Trucking's Technology and Maintenance Council

If there is one bible that governs the maintenance of heavy trucks, it comes in the form of the Recommended Practices developed by the Technology and Maintenance Council (TMC) of the American Trucking Associations. And the annual convention where these practices are developed has become one of the leading sources of information on the trucking industry’s maintenance and equipment trends.

Jobber News attended TMC’s recent annual meeting in Tampa, Fla., and compiled the following key trends.

A breakdown of parts purchases

A quick review of the purchase orders generated by fleet customers may offer jobbers some valuable insights into whether they have a fair share of the business.

Preventive maintenance supplies such as oils and filters should account for 25% of a fleet’s spending on parts, explains Stanley Kotas of Fleet Maintenance Services. Routine parts such as brake components, belts, hoses, lighting, mirrors, and exhaust systems should account for another 50%.

Another 5% of the budget, he adds, should be invested in predictive maintenance supplies such as fan hubs and clutches, with fleets relying on agreements with suppliers to stock related items. “You can’t have a transmission sitting around for six months, just in case.”

In addition to the 15% devoted to safety supplies, Kotas suggests that 5% of the parts budget should be set aside for convenience items including cigarette lighters, CB accessories, HVAC control, and seat cushions. These may seem like trivial items, but they will play a role in driver retention.

Active debate about anti-idling solutions

There is an ongoing debate about whether excessive idling should be addressed with diesel-fired bunk heaters, Auxiliary Power Units (APUs), or electric solutions that can feed cabs with everything from a cool supply of air to 120-volt power.

Each solution presents its own benefits and challenges from the standpoint of related component sales. For fleets making the right choice, the benefits can be considerable.

Wal-Mart weighed in with its experience. With 6,850 tractors consuming 530 million litres of diesel per year, the world’s largest retailer obviously has a vested interest in finding a way to burn less fuel. And since introducing APUs to offer climate controls and creature comforts, its fleet has reduced average idle time from 47% to 8.5%. (It is also meeting the requirements of a settlement in a lawsuit by Connecticut and Massachusetts, which had balked at excessive idling outside Wal-Mart stores.)

There have been other benefits, including drops in electrical service calls between 2004 and 2006, a 14% drop in the number of replacement alternators, and 7% reduction in replacement batteries.

Dennis Damman, director of engineering with Schneider National, prefers his fleet’s diesel-fired bunk heaters, in part because of costs below $1,000 per unit. The equipment is also easy to operate, burns a mere 0.26 litres of fuel per hour, and draws less than 1.5 amps of battery power to start.

Fleets interested in systems that use in-cab batteries to power HVAC systems will have other issues to consider, such as the need for bigger or better battery packs, says Bruce Purkey of Purkey’s Fleet Electrics. They can even be expected to place an entirely different focus on the way batteries are purchased.

“You’re going to have to look at batteries in terms of amp hours, and not just cold cranking amps,” he says, noting that higher output alternators may also be needed.

Expect biodiesel push, more mandated equipment

With the U.S. Congress now controlled by Democrats, American Trucking Associations (ATA) vice-president Tim Lynch is warning that federal mandates for new equipment, as well as pressure to use biodiesel, are probably going to become a new reality for the trucking industry.

Congress doesn’t have the budget to fund new programs, so it will undoubtedly begin turning to the private sector with a message of “we want you to do this,” he said in a keynote address.

That means a government that mandates solutions. Need to keep a driver awake? Put a device on the truck. Need to keep vehicles from rear-ending each other? Put a device on the truck. The related parts will undoubtedly end up on a jobber’s shelves.

A set of environmental priorities can also be expected, he added.

For proof of a changing legislative environment, Lynch points to the recent renaming of two subcommittees of the Senate Environmental and Public Works Committee to include the words “Global Warming.”

Since the agriculturally rich state of Iowa represents a key step in the upcoming presidential race, the ATA also expects candidates to promote the use of biodiesel.

Idling limited by refined hydraulics

More than 300,000 refuse vehicles collect North America’s trash and recyclables, with each vehicle consuming an average of 170 litres of diesel per day. That’s a waste when you consider that much of the fuel is consumed by idling vehicles that are powering auxiliary functions such as sweep and pack cycles.

An idling engine might need to rev up to 1,500 rpm to power a single hydraulic pump.

The operators of specialty vehicles, however, are finding a number of solutions that will limit such requirements.

Quebec’s Labrie Environmental Group, for example, has introduced the combination of a full-flow and variable displacement piston pump to power various PTO functions, says Walter Peterson, a market specialist with Parker Hannifin. The system will deliver the 25 gallons per minute needed to lift a bin of trash, or combine both pumps to offer the 40 gallons per minute needed to operate a packer, while the engine operates at speeds below 900 rpm. The power is also delivered in a package that’s smaller than a completely variable-displacement piston pump.

“The thrower [the employee who loads the trash] can initiate the hopper cycle at any time,” Peterson adds, noting that the vehicle can remain in motion during the action.

Since they require lower engine speeds, the systems are also quieter, introducing the opportunity to begin work earlier in the day, he adds. Transmission shifters will also last longer because vehicles don’t have to shift in and out of neutral for each function.

What can we expect in 2010?

Manufacturers are in the midst of designing strategies to address the next round of U.S. Environmental Protection Agency standards for diesel engines, which will be unveiled in 2010. This time, regulators will require another 85% reduction in NOx, along with related onboard diagnostic systems.

“We may not all be going in the same direction, but we’re all going toward the same goal,” says Caterpillar’s Brendt McClusky.

What this means is that post-2010 trucks will come fitted with yet another generation of equipment.

Approaches being investigated so far include:

*Selective Catalytic Reduction (SCR) — This technology, which is already being used in Europe, introduces a mixture of urea into the exhaust stream, where the heat of the exhaust converts the mixture into ammonia and water, enabling a chemical process that turns NOx into a harmless mixture of water vapour and nitrogen.

*Homogeneous Charge Ignition (HCI) — This hybrid of a gasoline engine’s spark-driven ignition and a diesel engine’s compression ignition involves mixing fuel before it’s injected into the combustion chamber. The result is a lower local flame temperature that produces less NOx. The process will require some precisely controlled valve timing, says Chuck Blake, Detroit Diesel’s senior technical sales support manager. “Sometimes you need to re-induct the exhaust and hurt your scavaging [the effect that pulls gases out of the exhaust].” However, the mechanical action of a crankshaft eccentric can be used to change the compression ratio.

*Hydrogen-Enabled Combustion (HEC) — “This is not ‘get some hydrogen and throw it in the tank,'” Blake stresses of the technology. Instead, HEC would use diesel fuel to generate hydrogen, which would be ignited by an electric spark in a “plasma reformer.” The highly charged ionized gas (plasma) would then be used to regenerate a trap designed to capture NOx.

*The Lean NOx Trap (LNT) — Eaton has announced that it is working on a solution that combines a fuel dosing unit, a fuel reformer catalyst, a Lean NOx Trap (LNT) catalyst, and an SCR catalyst. Essentially, the lower NOx is achieved in two steps: with the LNT and the SCR. Unlike systems that draw the ammonia from urea, the Eaton system would use the LNT to convert NOx into nitrogen and produce ammonia. That ammonia would then be stored in the SCR catalyst, converting any NOx that slips past the LNT.

Another jug on the shelf?

If North America’s trucking industry embraces the use of urea to meet the next round of vehicle emission standards, jobbers will need to stock yet another fluid for fleet customers.

A urea-based technology offers several advantages, says Volvo Trucks North America’s Mark Louzon. “The base engine you’ve come to know from the ’04 or ’07 world, that engine should pretty much remain the same.” Engine manufacturers would even be able to generate more NOx in the name of efficiency or fuel economy, and simply address the unwanted gas with the urea in a process known as Selective Catalytic Reduction (SCR), he says.

The question of what a urea distribution network would look like is still a matter of discussion among groups including the Alliance of Automobile Manufacturers, the Engine Manufacturers Association, and the Truck Manufacturers Association.

It’s believed that a 2010 engine would require about one part urea to 100 parts of diesel fuel. And if the European experience offers any indication (the fluid is already adopted as a solution on that continent), the urea will also cost about 50 cents per litre.

“A 1% usage is fairly minimal,” adds Blake. “It’s equivalent to windshield washer fluid.”

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