Motor Oil Question....

[racefan77]

Hi everyone. I changed my oil last weekend, and just noticed that I put in 5W-20 instead of the ussual 5W-30. I have done some research on the internet about what the difference is, and get a bunch of different answers. The general one seems to be that there isn't much difference and nothing to worry about, and some even prefer the 5W-20. It seems that the crucial point is with cold weather. It is currently spring where I live, so there isn't going to be any sub-zero cold starting, and also no extremely hot weather either any time soon. Should I drain out the 5W-20 and go put in the usual, or will this be fine as long as it is changed before the really hot weather? The car is a 1999 Lumina, and it was Quaker State Full Synthetic motor oil that was put in.

[Bob Riebe]

Hi everyone. I changed my oil last weekend, and just noticed that I put in 5W-20 instead of the ussual 5W-30. I have done some research on the internet about what the difference is, and get a bunch of different answers. The general one seems to be that there isn't much difference and nothing to worry about, and some even prefer the 5W-20. It seems that the crucial point is with cold weather. It is currently spring where I live, so there isn't going to be any sub-zero cold starting, and also no extremely hot weather either any time soon. Should I drain out the 5W-20 and go put in the usual, or will this be fine as long as it is changed before the really hot weather? The car is a 1999 Lumina, and it was Quaker State Full Synthetic motor oil that was put in.

You will be fine till your next scheduled oil change, or even longer.

[Rollo]

Should I drain out the 5W-20 and go put in the usual, or will this be fine as long as it is changed before the really hot weather? The car is a 1999 Lumina, and it was Quaker State Full Synthetic motor oil that was put in.

If you've got a '99 Lumina then the chances are that the car has probably done at least 100,000 miles. This means that the tolerances will have opened up and you probably need a heavier grade oil like a 10W-30 or 10W-40 even.
I'm wondering why you were puting in 5W-30 usually. That would indicate that you regularly experience temperatures below 40°F and need the lighter weight oil to help on startup.

If not, the lighter oil will just more than likely burn off a little quicker and you should probably think about topping it up with something a bit heavier part way through this oil change cycle.

Being a bigger +3 Litre V6, the need for a lighter oil isn't as great as the 2L and 3L in the Opel/Vauxhall Omega counterpart of the car.

[racefan77]

Very interesting, yes the car does have over 100,000 miles on it. I do live in a place that gets extremely cold, sadly for a good portion of the year (Winnipeg, Manitoba). I just have always used 5W-30 in all my cars because that is always what the manual and oil cap say to use. I ended up with 5W-20 because I was in a hurry and saw the shelf at the store with the 5W-30 sign, but I guess someone put a 5W-20 on there, and thats what I grabbed, my fault, should have checked. Either way. I am just unsure of exactly what the numbers mean, and when I pulled into the garage today, I happened to notice on the oil container that it was 5W-30, kinda paniced a little bit, and went looking for answers. Thanks for the help guys.

[racefan77]

Sorry, at the end of the post, I meant 5W-20, not 5W-30.