Probably the most important thing you can give your elderly car, aside from regular maintenance, is high-mileage engine oil. What exactly is high-mileage oil and when should you use it?

He said there are “distinct differences” compared to regular oils. “Most of the high mileage oil will have a seal conditioner ...

Is special high-mileage oil worth the extra price compared to a conventional lubricant? Z. George Zhang, Ph.D. and director of Valvoline Technical International thinks so. He said there are ...