CleanFUEL USA fuel system powers new Thomas propane bus
CleanFUEL USA’s liquid propane injection system is employed by the Thomas Built Buses propane Saf-T-Liner C2 school bus as well as the Freightliner Custom Chassis S2G medium-duty truck, both of which are now in full production.

The propane version of Thomas Built’s C2 uses CleanFUEL USA’s liquid propane injection system.
CleanFUEL USA’s liquid propane injection (LPI) system powers the Thomas Built Buses propane Saf-T-Liner C2 school bus as well as the Freightliner Custom Chassis S2G medium-duty truck, both of which are now in full production.
Company officials said that the CleanFUEL USA LPI fuel system is technologically advanced, fully integrated and factory installed, requiring no aftermarket modifications, for seamless integration and consistent quality. Both vehicles are EPA and California Air Resources Board certified.
“We are ecstatic that the S2G and C2 are in full production, as demand is strong in the fleet industry for propane-powered solutions that meet these two vehicles’ market needs,” said Curtis Donaldson, founder and managing director of CleanFUEL USA. “With a significant order bank and ever-increasing customer interest, the potential for both products is huge.”
The school bus and the truck are powered by an 8.0-liter, purpose-built engine by Powertrain Integration and an Allison 2300 automatic transmission with power take-off provision. The engine offers 495 ft.-lbs. of torque at 3,100 rpm and 339 horsepower at 4,100 rpm.
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