What happens when different oils are used?

[HKrpS13]

The other night I was doing an oil change on my friends 240SX and my friend made a mistake and got 3 quarts of 10W-30 and 1 quarts of 10W-40 and I found this out after I've put in the oil. Should my friend drain and fill it up with 4 quarts of the same oil or it's not a big deal?
By the way, What does the numbers stand for?

[autobahNESSA]

The other night I was doing an oil change on my friends 240SX and my friend made a mistake and got 3 quarts of 10W-30 and 1 quarts of 10W-40 and I found this out after I've put in the oil. Should my friend drain and fill it up with 4 quarts of the same oil or it's not a big deal?
By the way, What does the numbers stand for?


Its fine
thier both the same weight
10w(weight) 30/ 40 has to do with temperature differences from what I remeber.

you'll be fine untill your next oil change.

[HiPSI]

no problem with mixing, your engine will mix it all together nicely, lol

[HKrpS13]

thanks for your help. saved me from getting dirty.
what if the numbers on the _W was different?

[pr240sx]

You can safely mix all kinds of weights, no engine seizure or malfunction will occur
But dont make this mistake too often,
Now, mixing different brands with different weight could cause a problem. Some oil companies add additives and detergents that could break down harmfully in your engine.

But in case of emergency, different oil is better than no oil at all!!

[Replicant_S14]

it's 10W-37.5

Custom blend. I like it. :hyper: