By Garrett McKinnon
VehicleMD Staff Writer
Originally published in Winter 2011 issue
BMWs have them. Mercedes, too. And so do Audis, Volvos, Lexuses (Lexii?), Acuras and others. What are “they,” you might ask? Oil change indicator lights. And they’re not just confined to luxury makes, either. Almost every GM vehicle made since 2004 has come standard with the company’s “Oil Life System,” and companies like Chrysler, Honda, Toyota and others are increasingly putting oil change reminder systems in their cars.
But what do these little lights and flashing messages really tell you about the condition of your car’s motor oil? And how do they know when your motor oil needs to be changed? Osmosis? Magic? Lucky guess?
Regardless of the automaker, today’s oil life reminder systems all have one thing in common: They do not physicall ...[more]