Regarding different kinds of oil as fuel and as engine oil; no harm it seems and surely other types of oils can also be used in the engine as lubricant.
Fry and drive
When staff at a Welsh supermarket first noticed dramatic increases in the sale of cooking oil, they thought the locals were doing a lot of frying. They weren't. They were filling up their cars with it - not surprising, as it's only 42p a litre. Trouble is, if you don't pay duty, it's illegal. Jim White reports
Monday January 20, 2003 The Guardian
According to Mike Hebson, the manager of Asda's store in Swansea, south Wales, there was no reason to be suspicious that sales of the company's cheapest bottles of cooking oil were running 20% higher than the previous year, way above any other store in Britain. "We just thought it was one of those things," says Hebson.
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