Hi,

I have a 2007 S60 2.5T with ~100,000 miles on it and when I did the oil change yesterday by mistake I used the 5W-20 oil for my sons car instead of the 5W-30. Should I drain and refill or leave it until the next oil change? What possible problems could occur?

Thank you!

 

the 20 refers to how thin the oil will be at temperature and the 5 refers to how thick the oil will be when cold. The owners manual recommends either a 0 or 5 weight on the bottom and a 30 or 40 on top. So the impact of 5w20 will be based on your driving requirements and climate. If you live in a hot climate or with lots of hills, your proper oil should be a 5W40. If you live where its cold in the winter and you see below 0 F regularly, you will want a 0W40. If your temps don't regularly go above 85F, then a 5W30 is recommended. So worst case is you drive the car hard and the oil thins too much as it heats up to give you spotty coverage and you risk some premature engine wear. If its just going a few miles down the road say to school, then there's little risk of heat build up. Since turbos do tend a be a bit harder on oil, I'd probably do a quick drain/fill and use 5W40.

Considering you just did a change, you could do a drain/fill reusing the filter - just don't overfill since about half a quart will stay in the filter.

 

Oil's cheap. Just change it.

 

Interestingly, I just saw something regarding the newer Volvo 4 cylinders which do use the 5w20 oil and Volvo explicitly says do NOT use (with the "not" in bold) on 5 or 6 cylinder engines... So the consensus is, oil's cheap, just change it.