One of the beautiful things about tanks is that the engines are designed to have a high tolerance for low quality fuels. From what I understand most Russian tanks could be powered off a kerosene/diesel mix though with worse performance. I know that the M1 Abrams can use almost any type of fuel because it uses a bloody turbine engine.

Just bear in mind that there is a reason why the US maintains a strategic reserve of oil though it will be interesting to see how they plan to power tanks in the future if they decided to go away from oil based fuels.