Fleet Management News & Business Info | Commercial Carrier Journal
Issue link: http://read.dmtmag.com/i/599511
70 commercial carrier journal | november 2015 EquipmEnt: 6x2 AxLES Other issues were not the drivers' fault; early compatibility problems with the drivetrain were partly to blame. "You have to set the entire system up right," he says. The engine and transmission must be optimized for a 6x2 axle, and Nussbaum also spec'd electronically-controlled air suspensions to control how much weight is on the drive tires in any given situation. "Any traction event dumps air off the tag axle and moves it to the drive axle," Braker says. "You want as much weight on the drive axle as possible at all times." While good torque management is important, tire spec'ing also can play a huge role. "A good tire management program working with a tire manufac- turer can go a long way on that front," Perry says. "You want the most aggres- sive tread profile on your drive tire that you can find." Perry warns that doing so, however, isn't as easy as it sounds. "This can be a big problem," he says. "At first, our tire wear results were very discouraging, but we've come to find that if handled cor- rectly, you can eventually manage 6x2 tire wear back to equilibrium with 6x4 wear." Roeth attributes most tire wear issues associated with 6x2 axles to bad timing. Many fleets seeking to maximize fuel economy started running SmartWay- certified low-rolling-resistance tires on their initial 6x2 tests. "That wasn't a good mix," Roeth says. "In some cases, drive tire wear actually doubled or worse. The answer here in most cases is more tread with a higher rolling-resistance number combined with programming engines and trans- missions to manage torque at launch." Taking those steps will get tire wear issues under control, he says. "Any fuel economy hit you take with higher- rolling-resistance tires will be more than offset by the gains you get running the 6x2 axle." The final nega- tive cited by fleets testing 6x2 axles concerns resell values. Because these trucks only work well in targeted applica- tions, finding buyers for used trucks with single drive axles can be a problem. "You just can't market them like any other vehicle out there," Perry says. "You have to find a buyer with the same type of operation and duty cycle you have, so it does limit your resell prospects." OEMs have tried to address this issue with conversion kits to switch a 6x2 setup to a 6x4 more easily. If the EPA study proves to be accurate, resell issues are likely to be a short-term problem as more fleets switch to 6x2 axles, Roeth says. "You can't get high fuel economy and have a truck that will be everything to everybody," he says. "These are really highly specialized vehicles capable of getting up to 6 percent better fuel economy than a comparable truck equipped with a 6x4 axle. That's why I believe this issue will mitigate over time." The numbers Nussbaum obtained from its earliest 6x2 tests convinced the company to adopt the spec. "We were getting a ½-a-mile-per-gallon fuel economy improvement right off the bat, and those numbers still hold true now," Braker says. "We won't buy any more 6x4 tractors going forward unless they're slated for a specific duty that a 6x2 truck can't fill. We may take a hit on the back end, but we're more than making up for that in the meantime with the fuel we're saving today." Rocky Mount, N.C.-based Eagle Transport Corp. found that 6x2 axles delivered significant fuel economy and payload improvements. KIENE K-1320 Battery Grip The safe way to handle heavy truck batteries! 325 S. Fairbank Street, Addison, IL., 60101 Phone: 1-800-264-5950 • 630-543-5950 • Fax: 630-543-5953 www.kienediesel.com • e-mail: alanc@kienediesel.com Ergonomic handle for comfortable lifting and transporting Heavy duty truck batteries are tough and dangerous to handle. They're heavy, awkward and when they're squeezed into a battery box, getting a grip on them for lifting, is a real challenge. and lifting by the terminal posts damages the battery. • Fits all heavy-duty truck batteries. • Compact design ts into tight spots. • Safety and cost savings from KIENE. The K-1320 Battery Grip solves these problems! Includes an ergonomic handle for comfortable lifting, textured grippers and a powerful controlled squeeze that provides a safe secure grip. Just clamp it on and you're ready to go. Easy and quick to use . . . Clamp it on and you're ready to lift! MADE IN THE U.S.A. Textured grippers and powerful, controlled squeeze provide a safe, secure grip Kiene_CCJ1115_PG.indd 1 9/28/15 2:09 PM