Question is do you trust the dealer? What oil are they using? When I purchased my X5 CPO last spring, they (the stealer) changed the oil/filter etc for it to be offered as CPO. I changed everything out again myself soon after purchase because I don't trust them. Guess what I found? My filter had obviously NOT been changed. The fins on the media were all splayed apart and frayed, looking very worn and very used. It had seen at least a 15,000 mile interval by the previous owner maybe more, who knows, and if I had not changed it out, could have had to withstand another 15,000 miles. By the looks of it, I believe it would have very likely failed.

Ask yourself why the dealer would offer a change at $90.00? They are cutting corners somewhere most likely. Add the price of oil/qt + filter. Add in cost of Labor and iIt doesn't add up. It may be a loss leader with the intent to get you in the door and then charge up for some other service. Dealers are about one thing, and that is making money off of us, the customer. Most people who do there own oil changes do so because they know it was done right, and in the process usually save $$$. Everybody has to find their own comfort zone.

A quick search will show at a minimum 4 approved oils for use. You do not have to stick with the BMW 5W-30 (castrol), but it is good oil.

I believe (as do many others) that you should definately stick with OEM for the filter. The oil is a different story. You have choices. Just change it at teh 1/2 interval or 7,500 miles.

Castrol 0w-30, mobil 1 0w-40, penzoil platinum 5w-30 are 3 that will work and can be found on sale.