I have had similar thoughts/questions regarding these types of products. I have read a number of past discussions on this board regarding products targeting fuel and oil change service. In my last three cars, all SAABs, I used BG products. Specifically, the oil change service, at 30k miles. I am about to hit 30K in my X5 this month. On one hand, based on my research on this website, I will most likely not do the BG oil change service at this time. On the other hand, I have used the Chevron fuel system cleaner every 4K miles.

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Current: 2014 X3 35i, Titanium Silver, M Sport, Cold Weather, Premium, and Technology packages.

Previous BMW: 2006 X5 4.4, Stratus Grey, Nav, Sport & Cold Weather packages, BMW Running boards, Intravee II, Michelin Latitude Tour HP.