I am wondering if I can use 10-40 dino motor oil in california.
I normally use 5-30 in winter & 10-30 in summer. will using 10-30 cause any problem.

Oil is havoline 10-40 DS.

 

Absolutely. It won't harm anything other than the wallet as you may lose a bit of gas mileage.

 

As long as you don't try to start your car when its cold and the temperature is below about 32 degrees F, you should have no problem.

Normally you would only want to use motor oil that heavy when you are driving in very hot conditions (temps above abour 90 degrees F and often up above 100) or your engine was worn and you wanted to try and decrease oil consumption by using a heavier motor oil.

So the question is, why do you want to use oil this heavy?

 

I am in california and we never run into sub zero temps. Only reason I was looking for 10-40 is that I am out of 10-30 oil have 10gallos of 10-40 available @ hand.

 

use it. you will be fine. as it is dino it might even shear down to a thick 30wt anyway.

 

Havoline DS seems to thin out unlike their old formula which is good if you are going for 10W40.

VQs seems to like thicker oils, I was on 10W30 for a very long time but recently switched back to 5W30 since they all cost the same. There was no improvement in MPG.

 

You could mix it with a thinner oil, just to be safe.