lpg
dont know wether this is any help to you i recently sold a petrol disco with lpg 3.9v8 I didnt rate it you definitly lost power and fuel consumption is approx 80% of normal I understand to convert diesel is alot more complex I dont think its worth the effort myself Iran a old deisel disco for years a good old tub but I rate this r3m much higher although the disco suspension was better ,cheers