All you need to know about 10w30 synthetic oil What is 10w30 engine oil? Lubricating oil with the label 10W30 has a strength rating of 10W only when the engine is cold and 30 when such a vehicle is heated. This is distinct from oil with the labelled 5W30, which has a lesser thickness at 5W whenever the engine is cold. 10w30 maintains excellent engine performance. Cutting-edge 10w30 motor oil with remarkable cleaning power, take precautions, and actual quality, 10W-30 is made to keep engines operating like new. According to Valvoline, an engine that runs more effectively might lead to significant savings at the pump because the friction modifier is more durable and slicker. For which use is 10W-30 lubricant advised? As it can endure extreme heat for a longer duration without affecting the vehicle's efficiency, 10w30 is a multi-grade radiator fluid that is perfect for massive engines. The thickness rating of this lubricant is 10 in freezing climates and 30 in hot weat...