Heavy Duty Trucking

JUL 2014

The Fleet Business Authority

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www.truckinginfo.com JULY 2014 • HDT 35 position of Canada's top carriers. Company president and owner, Louie Tolaini, a veteran driver who started trucking the late 1950s with a truck that didn't even have a driver's door, says he's quite im- pressed with the SmartAdvantage combo so far. "It's the first time I can remember a manufacturer promising something and the product performing even better than they said it would," he says. "Drivers complain about their seats, for heaven's sake, but I haven't yet heard a complaint about this new engine and transmission." The SmartAdvantage uses an interesting trans- mission that has a lot in common with the manual version, called Fuller Advantage. Eaton's Ryan Trzy- binski, Product Planning manager for NAFTA Com- mercial Vehicle Business, says the Advantage concept for both products is based on a new precision lubrica- tion system that sprays lubricant directly into the gear mesh rather than relying on the traditional oil bath to splash lubrication throughout the case. "The reduced churning losses with the precision lube system can improve fuel economy by 1.5% to 2%," he says. "On top of that, the oil cooler has been eliminated, saving more weight and up to 12 feet of tubing. We also changed some non-stress bearing parts of the housing from cast iron to aluminum, saving a total of about 82 pounds on the SmartAd- vantage system." The difference between the manual and automated versions of the Fuller Advantage transmission is the final gear ratio and the step between 9th and 10th gears. The manual version has a 0.73:1 final ratio, while the automated version used in the SmartAdvan- tage powertrain has a 0.80:1 final drive. The step between the top two gears is 26% rather than the more traditional 37% step found in the manual. While the intermediate-sized 26% step between 4th and 5th and 9th and 10th might baffle an inexperienced driver using a manual shifter, the automation handles it with aplomb. "We went with a smaller step between the top two gears to keep the engine within the sweet spot of the fuel map as much as possible," says Trzybinski. "We worked more closely with Cummins than we have ever done, sharing fuel maps, grade and mass calculations and more, to downspeed the entire drive line. Our goal, using a 2.64:1 drive axle, was an engine speed of 1,145 rpm at the fleet's intended cruise speed. It will shift between 9th and 10th more often than a traditional overdrive, but that's inten- tional to keep the engine speed in the most fuel-efficient range as much as possible." The truck I drove had a slightly different axle ratio, 2.92:1 rather than 2.64:1, likely because of Canada's high- er gross weights and dearth of Interstate-like highways. I • Cummins ISX15, 450 hp @ 1,800 rpm / 1,550-1,750 lb-ft @ 1,000 rpm ST2 • Fuller Advantage FAOM15810S-EC3, 10-speed automated • 1810 HD driveline • Dana DSP41, 40,000-lb axles 2.93:1 ratio • 65 mph max in top gear, 62 mph max cruise speed • GCW: 81,080 lb weighed on a Cat scale (legal in Canada) SPECIFICATIONS Eaton's Advantage driver interface is easy to use, and the upshift and downshift are in exactly the right place. noted engine and road speeds of 1,200 rpm in 10th gear at 62 mph, 1,075 rpm in 10th gear at 55 mph, 1,500 rpm in 9th gear at 62 mph and 1,200 rpm in 9th gear at 50 mph. Gearing the truck the way Eaton recommends would produce engine speeds about 50 rpm lower than I observed. Cummins says peak torque in the top two gears is 1,750 pounds-feet at a fuel-sipping 1,000 rpm. That gives the engine plenty of latitude before downshifting. Cruising on level ground, the ISX usually drifted down to 1,050 before downshifting. On a slight grade the transmission down- shifted from 10th to 9th at 1,050 at 58 mph. There are no hills anywhere close to where I started in Winnipeg that would demand a downshift from 9th to 8th, but I did run over a railroad overpass -- about 2%, I estimate -- several times at different speeds to simulate a sustained pull. Starting into the hill at 50 mph in 9th gear, it downshifted into 8th at 1,050 rpm. From a full stop up to cruise speed, this transmission proved to be the smoothest-shifting Eaton automated I've ever driven. I don't think the engine ever exceeded 1,300 rpm under normal, unhurried acceleration. With my foot right into it, it climbed to 1,400 a couple of times, but that was the exception. The truck I drove had an rev limiter set to 1,600 rpm,

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