As BMW recommends 91 octane in X5s, I wonder what lower octane gas as some of you are putting in your X's will do to an engine over a long period of time. If you have any mechanical problems with your engine due to lower octane gas, can BMW determine this and claim the problem is not covered under warranty due to lower octane.

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- 2005 X5 4.8is: LeMans Blue, Black/Blue Alcantara Leather Interior, Navi, Retractable cargo floor, Rear Side Impact Air Bags
- 2011 335i Sedan: Vermillion Red, Navi, Beige Leather Interior, Harmon Kardon Audio, Fully Loaded
- 2006 330xi Sedan: Titanium Silver, Navi, Dakota Leather, Fully Loaded
- 1987 Yamaha: Virago 700cc