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aimeef09
By aimeef09 | AA Member | 9 Posts | 4 September 2013 at 1:49pm

Hi Jack

Many people swear by putting premium fuel in their cars (95/98 grade) instead of 91 as it's "better" for the car, is this the case?
I've looked in the user manual of my car (2009 Mitsubishi Lancer VR) and it says to put 91 in it, surely they would recommend 95 or 98 if that was better? Also the fuel flap says "Use 91 octane".
I can afford to use higher grade if it ends up being better long-term, but I hesitate to do so when the manual says use 91.

ABayliss
By ABayliss | AA Expert | 2169 Posts | 4 September 2013 at 2:09pm

There is no advantage for you to use a higher grade of fuel than that which the manufacturer recommends. By the same token, there's no detrimental effect either, but testing we have done has found that it will be more expensive for you to use the higher octane fuel. Even though your car will travel slightly further on a higher grade, it will still cost more to run it on the higher grade.
If the manufacturer states 91, then use 91.