Hi Robert - I've just converted a Citroen C5 X7 (150K miles) to LPG (sorry Lexus owners for invading your forum) and it is supposed to take a 0W30 (ACEA C1) engine oil. I was wondering whether using a 0W40 or even a 5W50 would be preferable. Clearly a bit more fuel consumption but would the wear of parts be significantly reduced. BRC supplier says just to use the same oil as in a petrol engine, but I seem to burn more oil when running on gas. I'll probably test the Ow/40 Mobil 1 but I am tempted by the 5W50 Mobil 1 too.
