; (21) retrofitting advanced technologies onto existing truck fleets; (22) advanced boosting systems; (23) engine down speeding; and (24) integration of these and other advanced systems onto a single truck and trailer platform. 9. Class 8 truck and trailer systems demonstration (a) In general The Secretary shall conduct a competitive grant program to demonstrate the integration of multiple advanced technologies on Class 8 truck and trailer platforms, including a combination of technologies listed in section 8. (b) Applicant teams Applicant teams may be comprised of truck and trailer manufacturers, engine and component manufacturers, fleet customers, university researchers, and other applicants as appropriate for the development and demonstration of integrated Class 8 truck and trailer systems. 10. Technology testing and metrics The Secretary, in coordination with the partners of the interagency research program described in section 8— (1) shall develop standard testing procedures and technologies for evaluating the performance of advanced heavy vehicle technologies under a range of representative duty cycles and operating conditions, including for heavy hybrid propulsion systems; (2) shall evaluate heavy vehicle performance using work performance-based metrics other than those based on miles per gallon, including those based on units of volume and weight transported for freight applications, and appropriate metrics based on the work performed by nonroad systems