Viscosity. 5W-30 is a "thinner" oil than 10W-40 is.
The main difference between 10W-40 oil and 15W-40 oil is that 15W-40 oil has a higher viscosity than 10W-40 oil. 10W-40 oil allows the engine to run freely.
The 10W 40 oil is thicker and is thought by many to be more efficient.
any 10W-30 Motor Oil
Usually no difference except that later model vehicles require a multi-viscosity oil (5w-30, 10w-30. etc) while the regular 30w is recommended for small engines such as a lawn mower.
it is the additives they put in the oil
no
The weight of the oil when it is cold. The 15w is a thicker oil than the 10w when it is cold.
regular 10w 30 motor oil
One quart of Mobil Special 10W-40 motor oil weighs 1.8 pounds. Not all motor oils have the same density, and one gallon of motor oil will weigh between 6 and 8 pounds.
10w-40
10w 30
Yes