Should You Warm Up the Car Before an Oil Change?

[AdalineFitz]

It is recommended to warm up the car for about 5 minutes before changing the oil, as this helps drain the old oil more thoroughly. The benefits of warming up the car before an oil change include: 1. Oil is a viscous liquid, and at lower temperatures, its viscosity increases, making it harder to flow out when the oil pan drain plug is removed; 2. There may be sludge in the engine, which softens when the car is warmed up, allowing it to be expelled along with the old oil. Engine oil, also known as motor oil or engine lubricant, is a substance enhanced with additives in base oil, primarily containing anti-wear agents, detergents, dispersants, and multi-grade viscosity index improvers. Engine oil is used for lubricating internal combustion engines.

[IkerMarie]

I've been driving for over a decade, and I always warm up the engine before an oil change. When the oil is warm, it flows better, allowing contaminants to drain out with it. Cold oil is as thick as honey and won't drain completely. But be careful not to overheat it—just turn off the engine when the temperature gauge reaches the midpoint. Last week, my neighbor made the mistake of changing the oil while the engine was cold, and the next day, strange noises appeared. Actually, the safest method is to wait about 15 minutes after turning off the engine and then unscrew the oil pan drain plug while wearing thick gloves to avoid getting burned. In extremely cold winter conditions, you should warm up the engine a couple of minutes longer to ensure it's fully heated.

[McDelaney]

As an experienced DIYer in oil changes, I usually warm up the engine for five minutes first. This thins out the old oil, allowing it to drain more thoroughly. But be careful not to overheat the engine – it's too dangerous to loosen the drain plug at high temperatures. Last time, I rushed and started just ten minutes after shutting off the engine, resulting in hot oil splashing on my arm and leaving a red burn. Now I always wait twenty minutes after turning off the engine, checking that the hood isn't too hot to touch before starting. Remember to turn the drain plug counterclockwise to loosen it, and use a cloth to prevent slipping. If the drained oil looks like sludge, it's a sign you should have changed it sooner.

[SanChase]

When I first bought the car, I used to struggle with this issue. Later, a mechanic gave me an analogy: 'Isn't it hard to pour out cold hotpot oil? Engine oil is the same.' So now, I always start the car and let it reach normal operating temperature before changing the oil. Just remember not to change the oil with the engine running—turn it off and wait for the temperature to drop a bit before proceeding. This ensures the oil drains completely and allows for accurate measurement when adding new oil. Also, winter and summer are different; in sub-zero winter temperatures, you'll need to extend the warm-up time. If you're using full synthetic oil, changing it when the engine is cold isn't a big deal, but with mineral oil, you better warm up the car properly.

[McMalia]

In the auto repair industry, we always say to change the oil when the engine is warm. When the engine is cold, impurities in the oil settle at the bottom of the oil pan, and only a warm engine can flush them out. Here's a practical method: turn off the engine when the coolant temperature reaches 90°C, wait for ten minutes, then start the operation. If you wait too short a time, the oil temperature will be too high and can cause burns; if you wait too long, the oil will solidify. Use a hex socket wrench to loosen the oil pan drain plug—it’s the most convenient tool. Avoid using an adjustable wrench, as it can easily slip. Also, check the color of the drained old oil. If it’s as black as soy sauce, it means the engine needs cleaning.

[McJosie]

I remember my grandpa used to say that changing engine oil requires warming up the car first. The principle is simple: when the oil gets warm, it thins out and flows faster, allowing over 95% of the old oil to drain out. I always drive a short distance of about two kilometers before shutting off the engine, then wait until the dashboard temperature drops to around 50 degrees before starting the oil change. Be especially careful with older cars—the rubber seals become brittle at high temperatures, and rushing to loosen the bolts might damage the oil pan. Modern turbocharged cars don't require such meticulousness, but for traditional naturally aspirated engines, changing the oil when warm ensures a more thorough job. Oh, and after the change, remember to let the car idle for two minutes to allow the new oil to circulate throughout the system.