Fleet Management News & Business Info | Commercial Carrier Journal
Issue link: http://read.uberflip.com/i/409540
50 COMMERCIAL CARRIER JOURNAL | NOVEMBER 2014 C O V E R S T O R Y : F U E L E C O N O M Y S U R V E Y 2 Trailer side skirts Trailer side skirts have gone from curiosity to common- place in just a few short years, earning them a No. 2 ranking in CCJ's online poll. While early aerodynamic efforts targeted the tractor itself, streamlining what is essentially a long rectangular box proved to be a more problematic issue. Trailer side skirts were the first seri- ous attempt to streamline the airflow moving past the dry van trailer's bot- tom to eliminate drag and turbulence. As with other aerodynamic devices, side skirts are designed to allow the truck and trailer to move more ef- ficiently through the air, thereby putting less demand for power on the engine, which in turn burns less fuel. While early side skirts suffered from durability issues, the latest generation is engineered to achieve greater ground clearance to reduce the chance of im- pact damage. Utility Trailer offers a proprietary line of skirts designed to work with its family of dry vans. These skirts feature a galvanized high-tensile steel bracing system that allows the side skirt to flex both inward and outward and to be bent back if damaged. The skirt also is manufactured with a UV-protected bi- directional fiberglass reinforced plastic construction, while its forward edge is bolted with a spring attachment at the support leg assembly. Side skirt manufacturers say the devices can boost overall tractor-trailer fuel economy by more than 5 percent in most applications. 3 Aluminum wheels It's all about weight control when it comes to the third most popular fuel-saving spec. Robert Flynn, director of product marketing for Accuride, says that while aluminum wheels can cost up to three times more that those made of steel, most long- haul fleets looking to lower a tractor's weight are willing to pay that premium. Flynn says Alcoa's most drastic weight savings package with aluminum wheels is a 14-inch wide-based tire configu- ration that cuts a drive axle's typical weight from 130 pounds to 58 pounds, which works out to a total weight sav- ings of 1,400 pounds per vehicle. Those numbers work for fleets even more when fuel and maintenance savings are considered. Flynn says that while fleets typically see a 30 to 40 percent upcharge for aluminum wheels THE RUNNER-UPS A multitude of other highly effective specs can help boost overall fuel economy. Here's a rundown of other technologies in CCJ's online poll that didn't quite make it into the winner's circle. Automated manual transmissions The surge in popularity of AMTs is rooted in several factors, driver reten- tion and safety among them. But another benefit for fleets has been the potential fuel savings they can provide. When it comes to fuel economy, a good driver on a good day can beat an AMT, but day in and day out, the AMT can give every driver respectable mpg num - bers. Experts say an AMT can increase a vehicle's fuel economy by as much as 5 to 7 percent. Automatic transmissions Fully automatic transmissions differ from AMTs in that they have a torque converter instead of a computer-actu- ated clutch. Proponents claim this gives automatic transmissions a smoother ride than AMTs. Overall fuel economy is virtually identical to AMTs, however, with 5 to 7 percent increases being the norm in fleet operations. High-ratio rear axles High-ratio rear axles are engineered for top-end speed and efficiency and require less engine horsepower to get a truck moving and keep it at cruising speed. While the tradeoff is a loss in low-end torque, many nonvocational fleets like the modest fuel economy gains they offer in long-haul applications. Centrifugal oil filter While centrifugal oil filters aren't com- monly considered as fuel-economy enhancement devices, these highly efficient bypass filtration systems keep engine oil cleaner for longer periods of Utility Trailer offers a proprietary line of skirts designed to work with its family of dry vans.