Thanks for reading this post in advance, I picked up some 10w-30 Quaker State QTorque Power for 4x4 or trucks synthetic motor oil for a really good price at my local store. Can I use this oil in my van even though the manual recommends 5w-30. What kind of impact will it have on my engine. Will I cause any damage to it. I've read in a couple of chiltons car repair manuals, that if your engine accepts 5w-30, you can change the oil out with 10w-30 depending on the engines operating temperature. Also will synthetic have any adverse effects, make the engine work harder, or other bad things when used with the grade I purchased. Again thanks for reading this post and any help provided will be helpful.

 

The first number in the series is the oil's cold cranking ability. 5W is thinner than 10W. The second number is it's viscosity at operating temp. They are both 30W so it doesn't matter from an operating stand point. You just match the first number to the temps encountered in your local area.
One of the points for using synthetic is that molecularly it is all about the same size instead of being many sized as with dino oil. Having all the same size molecules makes for less friction as the oil circulates. Synthetic works easier in your engine.
To answer your question about using 10W-30, it's fine as long as outside temps during it's duty cycle don't go below 0*F. Below 0* you would want 5W-30.

 

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