This paper considers the option to convert the diesel engine to LPG retaining the diesel-like behaviour. LPG is an alternative fuel with a better carbon to hydrogen ratio permitting reduced carbon dioxide emissions. It flashes immediately to gaseous form even if injected in liquid state for a much cleaner combustion almost cancelling some of the emissions of the diesel. Within Australia, LPG permits a much better energy security and the refueling network is widespread. In this paper, a latest heavy duty truck diesel engine with a novel power turbine connected through a continuously variable transmission to the crank shaft and fitted with a by-pass is modified to accommodate a second direct injector for the LPG fuel and operate full load with 5% diesel and 95% LPG. Results of engine performance simulations with diesel and diesel-LPG are presented. The engine retains the diesel performances while permitting the advantages of LPG in terms of particulate, carbon dioxide emissions and diversification of fuel supplies and energy security. (C) 2013 Elsevier B.V. All rights reserved.