Hi guys,

I just wanted to see what ya'll take on mixing engine oil is. i have heard mixing brands and end weight is bad (eg. mobil 1 5w30 and castrol 10w60) ..

but what about mixing 5w40 castrol edge and 0w40 castrol edge (hence both end weight is the same).
would this be okay?

thanks in advance !

 

don't mix weights. other than that, you are okay.

 

2.5w-40

 

As long s the 2nd number is the same, you're fine. The first number comes from the amounts of a couple of additives they put in the oil, and will just average out if you mix a 0w40 and a 5w40. When the second number is different, the actual base stock is different, and it's not advisable to mix..

 

for my DD camry i put whatever is going in it, for the Evo I will only use one brand and weight of oil.

 

atm im using castrol edge 5w40 and i still had a few qrts of 0w40 left from my previous change. my next change im going with different brand completely but im only mid way point through the interval and i was 0.5 qtr down so thought i'd jst top it up with the 0w40 and then change after the appropriate interval.

i was also jst concerned cos the 5w40 apparently is a grp3 full synthetic while the 0w40 is known to be grp4 ?

anyways, thanks for ur input guys ~

 

Engine oil is a vital part of an engine's life. Why would you risk mixing oils?