Heavy Duty Trucking, June 2018

HDT JUNE 2018 50 WWW TRUCKINGINFO COMa fuel sipping tractor trailer is really a sum of its parts and every little tenth of a mile can eventually help pay big dividends over the long haul Roeth highlights some of the strategies used by the Run on Less participants to reap big gains Big gains via the drivetrain As effective as automated transmissions are in saving fuel their fuel economy potential increases dramatically once they are combined with downsped transmissions and predictive and adaptive cruise control systems The concept of a downsped transmission is pretty simple really The fewer rpms a diesel engine turns at highway speeds the less fuel it burns Of course the fewer rpms an engine is turning the less horsepower and torque the driver has to work with in terms of getting a tractor trailer moving and maintaining cruising speeds Thats where automated transmissions combined with lower gear ratios come into play One disadvantage to a downsped powertrain is increased vibration and associated shock loads to driveline components Automated transmissions can be programmed to compensate for lower torque and deliver smooth shifts while allowing engine speeds as low as 900 to 1000 rpms at 65 mph According to NACFE this technology can deliver between 3 6 or a half a mile per gallon boost in fuel economy Adaptive and predictive cruise modes take the power of automated transmissions even further These advanced driving systems use both radar and GPS technologies to keep a tractor trailer operating as efficiently as possible regardless of traffic conditions or geography Adaptive cruise control keeps a close electronic eye on vehicles in front of the tractor trailer and adjusts speeds to compensate as they speed up or slow down The idea is to keep the driver in cruise mode at all times and avoid burning fuel unnecessarily as a driver brakes and then applies full throttle to get back up to cruising speed Predictive cruise control uses real time vehicle data combined with GPS information to look and plan ahead and set gear shifts and throttle inputs in preparation like that but thats really what this thing was No aerodynamics at all The wheels werent aligned And I wasnt happy about it But the Run was about real world trucking So I had no choice but to deal with it If youre feeling sorry for Morrow dont He still managed to turn in numbers well over 9 mpg during the three week event It ended up being the real world in the extreme Roeth says We dealt with two hurricanes during the run straight line winds highway congestion and yes Joels trailer Which we calculated cost him about 15 mpg by the end of the challenge But even with all that going on which are the conditions that truck fleets and drivers deal with day in and day out we still managed to achieve a combined average of 101 mpg for all the trucks that participated in the Run on Less event Which proves that these fuel efficiency technologies and components can deliver big savings for North American fleets out there hauling real freight on real routes with real drivers behind the wheel The good news is there are a lot of fuel economy options on the table depending on your application The bad news is that not all of them will deliver big returns But Transport Inc PepsiCos Frito Lay division Hirschbach Transportation Mesilla Valley Transportation Nussbaum Transportation Ploger Transportation and U S Xpress All the trucks involved in the run were equipped with commercially available technologies that are available today We wanted to have some fun and find out whats possible in terms of mpg running current equipment today Roeth says We went to great pains to make sure that everything on the trucks was validated and fair There was no sneaking stuff onto the tractors Suppliers and OEMs werent allowed to put prototype or experimental equipment on the trucks And the trucks ran normal routes in a variety of applications all over the country Once the challenge began drivers had to make the best of whatever cards they were dealt in the course of normal fleet operations For example Joel Morrow director of research and development for Ploger Transportation was in the hunt for the lead position in terms of mpg when bad luck came his way I had one of our aerodynamic trailers on one of the runs when I had to drop it and hook up to this old trailer that was an absolute piece of sh he says laughing I shouldnt use language The NACFE Run on Less Challenge wrapped up at the North American Commercial Vehicle show last September Despite hurricanes and at least one far from ideal trailer the trucks in the fuel economy run averaged over 10 mpg overall RUN ON LESS PHOTO EVAN LOCKRIDGE