Edited by Jeff Yip

Q: My 2007 BMW 525i has reached 10,000 miles and I was concerned that the oil service light hadn't come on. When I tried to make an appointment for an oil change, the dealer informed me that they wouldn't do it until the oil service light triggered -- and this apparently occurs between 15,000 to 20,000 miles! I'm worried that that's too long. Should I change it anyway?

A: Welcome to the 21st century. While it's nice that BMW covers full scheduled maintenance for the warranty period (four years or 50,000 miles, which ever comes first), you've discovered that this means as few as three oil changes in those 48 months is acceptable -- at least to BMW.

Jeff Gee, a professional race/collector car fabricator and engine builder feels otherwise.

"I've been in this business a long time and have seen many engines torn down. I know oil technology, as well as engine management, has improved, but come on! 15,000 miles on an oil change? That's ridiculous! I went to the BMW dealership and asked the parts guy that I usually deal with what he thought. He agreed with me, and changes oil every 5,000 in his own BMW and lets BMW change it when the light does come on.

Change your oil at 5,000 miles if you are using synthetic. You're asking a lot from engine oil if you stretch it to 15,000. If I do nothing else to a car, I change oil religiously. My mom, my dad and I rack up tons of miles on our vehicles. My newer truck will hit 100,000 miles soon and it runs as smooth as new; my 2002 GMC Sierra has 230,000 and is still going strong. We put at least 150,000 to 160,000 miles on a car before we even consider a new one."

A Southern California BMW dealership told us that the alert flashes when the vehicle is first started (or just turn your key halfway). If it's blinking, it means that the oil is either low or needs to be replaced. The first service alert usually happens between 12,000 and 15,000 miles and that's when the first oil change would be performed. The system, the dealership's service rep told us, counts down miles, so you could change the oil at 5,000 miles without affecting the vehicle's official "babysitter."

Savvy shoppers looking for a pre-owned BMW ought to lean toward vehicles that haven't just been "maintained by the book" because there could be two: the manufacturer's and the one we car lovers go by.

Speaking of scheduled lubrication, engine oil was at the heart of a class-action lawsuit settled by Toyota Motor Corp. recently. The automaker agreed to compensate owners of certain 1997 to 2002 Lexus and Toyota models that suffered engine damage due to a buildup of thickened oil, or sludge. Toyota initially said the sludge was a result of poor maintenance, such as infrequent oil changes. Toyota's far from alone. With other automakers facing similar complaints from time to time, it's a great incentive to change the oil regularly and be able to prove you did.