> Even trucks and tractors can run on alternative fuels like natural gas. There are some very specific grades of machine lubricant, for which a large swath of industrial manufacturing abroad and domestically, utterly rely on--as in "cant be adjusted. cant be ported to alternatives. can't be rebuilt. would have to be gutted, scrapped, and completely replaced." Its not that there isn't alternatives, it's that the tolerances and processes these machines depend on, are *really* tight. Like sub-hairs-width. reference: worked in a machine shop making tooling for the oil industry.