Posted on 12/19/2025
Cold mornings and hot summer highway runs both put your engine oil to work in different ways. If you treat every season the same, the oil might still look fine on the dipstick, but it can be thinning, thickening, or breaking down faster than you expect. A few seasonal adjustments help your engine stay protected all year instead of just surviving to the next sticker date. Why Seasons Matter for Your Engine Oil Engine oil has to flow quickly on cold start, resist thinning when it is hot, and carry away contaminants from combustion. Temperature swings change how well it can do each of those jobs. In colder months, oil thickens, and your engine relies heavily on its “winter” rating so it can circulate right after you turn the key. Summer heat pushes in the other direction. Long drives, high speeds, and hot pavement raise oil temperatures and test the “weight” of the oil at operating temperature. We look at seasonal conditions because the same oi ... read more