I'm about to do my first oil change on my used car, but I have no idea if the previous owner used high milage oil or not. I want to put regular synthetic in but don't want to cause any leaks. Is there any way to tell if there's high mileage or regular oil inside?
He always had it professionally maintained by the dealer. If I called to ask would they know?
Thus is on a 2005 chevy avalanche
Call and ask for the service department. Ask them a hypothetical: If I brought in my vehicle model x, year x and mileage x, what oil would they use?
If you call, they may not give you any info over the phone over privacy concerns, scams, etc... I'd go there in person and ask what oil they've been servicing it with. Something along the lines of ; I just bought this Avalanche and I understand the previous owner serviced it here, can you please tell me what oil you used in the oil changes? provided it's local and easy enough to go there.
