Posted on 10/31/2025
Choosing engine oil used to be simple. Today, there are multiple viscosities, synthetic and conventional options, and specification codes that look like alphabet soup. The wrong choice can lead to noisy cold starts, timing problems, or deposits that build up quietly. The right oil helps your engine last longer, run smoother, and stay efficient. Here is how to pick correctly without the guesswork. Viscosity Numbers Are Not Just Labels The numbers on the bottle, such as 0W-20 or 5W-30, describe how the oil flows when cold and when hot. The first number with the W indicates cold start behavior. A lower first number flows faster on cold mornings, which helps protect parts during the first seconds after startup. The second number indicates thickness at operating temperature. Too thin when hot and the oil film can shear, too thick when cold, and it reaches moving parts too slowly. Your owner manual or oil cap lists a specific grade for your engine. Stick to it unless a ma ... read more