Just traded in my 08 xb with an Inline 4, but on that I used amsoil full synthetic extended drain 25,000 mile or a year. I let it go about 11,000-12,000 between changes. I just traded it in at 113,000 miles and it used no oil between changes. I traded it in on a brand new 2011 Ford Edge 3.5 V6. The dealership I got it from does what they call customer for life. so that includes oil changes every 5,000 miles. So that is what will be done on the edge... But I loved the amsoil product, still use the same oil in my fiance's 06 Mazda 6s with a 3.0 V6 has 60,000 miles and uses no oil between changes either however she only does 5,000-6,000 miles a year so it is done once a year.