if u mix 10/30 and 20/50 oil same manufacturer, what happens..

if u mix 2 different weight oils in same quantities what actually will u end up with?

15/40?

Average 10/30 = 20 add the remaining average of 20/50 = 35
Add the two sums of 20 and 35 which is = 55
Divide the total of 55 by two = 27.5
To confirm the math add all four "mix" numbers 10,30,20 & 50 and we arrive at 110, then divide by four.. and to answer your question "what happens" is the average sum of 27.5
Hence the actual oil volume will remain the same but the oil weights will be some what mixed, not such a good thing.
So there you have it ......I'm just say'n.

If you mix 20W-50 and 10W-40 for a short drive in 75 degree weather you will be fine. But just change the oil and add the correct viscosity for the temp you will be running in.

If you mix the 2 different viscosity oil's then it will explode once you reach 4,500 RPM's

Same as missing beers - a light and a lager plus an ale - NO PROBLEM. Mixing oil - same difference.

If I'm.... missing... beers, I'm concerned.

I'm missing beers- I thought I had a twelve pack, but there are now only nine bottles in the case. WTF?

DON'T MIX OIL VISCOSITY! They don't mix at all. It will cause serious engine surging as first the engine speeds up when the crank gets a lighter viscosity and then it slows down as the crank receives higher viscosity. Same with your cam and the lifters. Pretty soon your whole engine is out of sync and its is a major task to get everything lined up again.

That is why new Fords had to add "InSync" to all their new cars - because of the crappy oil people put in their cars. DON'T DO IT!







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