Heavy Duty Trucking, March 2018

VOCATIONAL parts of the country Fortunately fleets today have a wide variety of power options to choose from When deciding on engine displacement the duty cycle of the vehicle needs to be carefully considered Kenworths Swihart advises While 350 hp can easily be achieved with a 9L engine it may not last as long in rigorous vocational conditions as a larger 11L or 13L engine Swihart says fleets that run their trucks continuously throughout a workday and use a power take off PTO frequently may find larger displacement engines are worth the additional weight and cost On the other hand fleets running trucks that are driven to and from jobsites and shut down once they arrive may find a smaller displacement engine works just fine Because there is no one size fits all solution to determining the best engine choice for different vocations and duty cycles we do not see a specific trend for smaller or larger engine displacements Gerdert says And because there are so many different vocational applications to service she says Daimler Trucks North Americas Detroit division has focused on offering customers as many power ratings as possible in order to meet their needs from the 210 hp Detroit DD5 engine up to the 600 hp Detroit DD16 On the smaller end of the vocational scale Kevin Koester medium duty truck and Super Duty fleet marketing manager for Ford says hes seen a definite move in smaller displacement engines away from diesel to gasoline power Were seeing growing numbers of customers expand the use of gasoline engines for applications that had previously been diesel dominant Koester says And those fleets are discovering that gas engines can perform very well without the higher acquisition costs emissions equipment and increased maintenance requirements of diesel engines today Theres also the question of alternative fuels Natural gas for instance has seen adoption in the refuse world led by fleets such as Waste Management and Republic and Chicago based Ozinga is pioneering natural gas in ready mix HOW SUSPENSIONS ARE CHANGING Tough starts deep under the skin with vocational truck design Although the components that help these trucks perform day in and day out are tough tested and proven even they arent immune to change as two suspension manufacturers observe Vocational suppliers are seeing a trend away from mechanical suspensions to air ride suspensions says Jason Heath product manager Neway Truck Bus RV Suspensions Early air ride suspensions had reliability issues he notes prompting fleets to spec mechanical suspensions which were more robust but offered more uncomfortable rides Design improvements and more robust components have changed that he says with younger drivers and fleet managers turning to air ride suspensions more often One area where air ride suspensions today are very popular is in the oil and gas sector according to Steve Hampson director of marketing for Hendrickson where theres a need for a good ride and cargo stability combined with lateral stability and the ability to cross rugged terrain as smoothly as possible Air ride suspensions today provide a balance of features that deliver a good ride on the highway with good handling and cross country capability for heavy and severe duty applications Hampson explains Air ride suspensions can also weigh from 500 to 800 pounds less than a mechanical suspension making them a good choice for mixer dump and other payload focused applications Everything else on a truck seems to be getting heavier these days So air ride axles are an easy way for vocational fleets to regain some ground on the GVW front while getting a smoother ride in the process Fleets are also demanding lighter and more capable axles that are easier to install Hampton says noting that the latest vocational steer and lift axles from Hendrickson are 60 pounds lighter than previous axles and are designed to work more efficiently with air disc brakes which are being specd more often Heath says Neways parent company SAF Holland saw an opportunity to design lift axles in a way that would reduce installation time while taking up less space on the truck frame which has paid benefits for fleets because available frame rail space is shrinking We also see the industry moving over to lift axles that are fully plumbed from the supplier he adds And were seeing more interest in accommodating air disc brakes and fender brackets as well And then of course there is the newest emerging power option in medium duty all electric drivetrains International last fall announced a joint project with Volkswagen to develop a line of medium duty electric trucks and vans Its hard not to look at the automotive landscape today and see that things once considered farfetched are mainstream today Hillman says No one looks twice when they see a Tesla car on the street today And nothing breeds success like success Outside of their obvious appeal to fleets operating in areas with tough environmental regulations or for green focused customers Hillman says fleet managers experimenting with electric trucks and vans PHOTO HENDRICKSON Lift axles today are lighter smaller and can accommodate air disc brakes which are becoming increasingly common on vocational trucks today are finding they have very few moving parts and corresponding low maintenance demands Were seeing the first efforts now to scale up automotive batteries to more powerful longer lasting units more appropriate for trucking applications he says along with sophisticated software and battery management systems to help the trucks run productively Vocational trucks work hard in tough crowded and dangerous environments Given these demands its not surprising those fleet managers are looking for any edge to give them an upper hand in their daily grind And increasingly it seems theyre turning to modern technology to do exactly that HDT MARCH 2018 62 WWW TRUCKINGINFO COM