I needed a wheel alignment and figured I'd take advantage of the special and get an oil change while I was at it. Looking at the receipt today, it looks like this place filled me up with 5w20 synthetic. Why would anybody do this? I even have the factory cap that specifies 5w30. I live in upstate New York and it'll be getting cold soon. I've never run 5w20 in any car I've ever owned. Is it worth my time to go make a stink about this and get them to change my oil again with the right stuff or is this probably fine? I'm not happy about it but I don't want to take a whole Saturday morning and waste it if I don't really have to.

 

I wouldn't worry about it. Doesn't hurt anything as long as the motor has oil pressure. (tight enough bearing clearances; not all wore out) The difference between 5W-20 and 5W-30 is that the base stock is the same but the -30 has less "thickeners" to get it up to 30; meaning, more lubricant.

My son's Honda Accord (2007) uses 0W-20. Year round. Thin oil like that is quite common nowadays. After all, it IS the 21st century now.

It doesn't really get COLD COLD where you are; not like the Dakotas or Minnesota for example, or even Chicago; but in a place like those, it'd probably be better to run thinner oil like that in the winter.