By Bob Raybuck
Director of Technical Services
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Many times, similar vehicles that are purchased within a few years of each other are based on the same specification. Although using previous specifications may seem more efficient when purchasing or replacing a vehicle, you may ultimately overlook new and important changes related to design, technology and regulations that can impact overall vehicle optimization. The fast-paced technological changes we encounter today at work and in our everyday lives are equally prevalent in the commercial vehicle community. For this reason, it’s important to update specifications to reflect today’s vehicles, technology, and safety and emissions compliance.
Ensuring the most up-to-date specifications involves exploring questions such as
- What are current and future safety standards — Federal Motor Vehicle Safety Standards (FMVSS) and emissions requirements — that will apply to vehicle sizes I am specifying?
- What current and emerging technologies can help with safety and efficiency?
- What advancements in collision warning, automated braking, vehicle tracking, and fuel savings (such as automated stop-start or component hybridization) would be advantageous?
Asking questions like these at each procurement cycle will help you identify which new features would be beneficial to the vehicle’s designed application and should potentially be added to the specification. With multi-stage commercial vehicles, it is critically important to maintain accurate documentation to help ensure a vehicle has remained in compliance with applicable safety and emissions standards through the upfitting process.
When reviewing specifications, recognition of emission and safety standards is key as you could inadvertently ask your supplier to build a vehicle that cannot meet FMVSS and emission requirements based on size. As an example, preferred specifications may call for a gross vehicle weight rating (GVWR) of 10,000 pounds or less in order to ease driver restrictions. However, vehicles in this GVWR range must meet more FMVSS than those exceeding 10,000 pounds. Some standards related to vehicles with a GVWR under 10,000 pounds (such as FMVSS 208 occupant crash protection, FMVSS 216 roof crush, FMVSS 301 fuel system integrity and FMVSS 126 electronic stability control) entail complicated and expensive dynamic testing. For this reason, chassis OEMs provide specific requirements for meeting some of these safety standards, which include limiting total weight of the completed vehicle and placing limitations on size, weight, and center of gravity of truck bodies and related equipment. Vehicles may have strict limitations on maximum weight and frontal area of the completed vehicle in order to meet increasingly stringent emissions standards.
The chassis OEMs provide an incomplete vehicle document (IVD) and body builder documentation with detailed information on these limitations to assist in your specifications review. If vehicle specifications exceed these limitations, as provided by the chassis OEM, ability of the completed vehicle to meet mandated compliance regulations should be closely examined.
It’s important to maintain appropriate documentation on each upfitted vehicle as proof that the specification meets all safety and emissions requirements. If the specifications fall outside chassis OEM limitations, you should have a documented compliance pathway from the body company or upfitter. Documentation may include independent testing, engineering analysis, or simulations that have been performed and should contain a payload analysis to ensure your specifications have sufficient payload capability and a weight distribution analysis to verify no axles are overloaded.
A robust set of specifications can help procurement of the right truck for the right application. Well-crafted specifications add to vehicle reliability, translating into more uptime, reduced maintenance and greater driver productivity. However, the specifications must be timely and address new requirements in safety, emissions and advanced technologies to help guarantee the safest, most productive vehicles for each application.
NTEA offers access to publications and reference materials on current regulations, safety standards, and other technical issues at ntea.com. To learn more about the tools, resources and solutions available to members, visit ntea.com/memberbenefits.
Green Truck Association (GTA), an NTEA affiliate division, offers a variety of resources to educate its members on techniques and technology that can improve fleet efficiency, reduce emissions across time, and lower the risk of fuel price volatility driving up operating expenses. GTA fleet members can get involved in a data logger drive and duty cycle program that provides information on how vehicles operate in varying environments; find details at greentruckassociation.com.