Oil is the lifeblood of your car’s engine, lubricating critical components and keeping everything running smoothly. When it’s time for an oil change, one of the most important best practices is allowing your engine adequate time to cool first.
In this in-depth blog post, we’ll explore why cooling is vital, how long you should wait, techniques for faster cooling, tips for safe oil changes, and other essential information for keeping your engine healthy.
Why You Must Let the Engine Cool?
There are two primary reasons it’s crucial to let your car’s engine cool before changing the oil:
a. Hot Oil Flows Faster
When you run your engine, friction causes the metal parts to expand from heat. The oil also becomes extremely hot – up to 250°F or more! This high temperature makes the oil much thinner than at room temperature. So if you drain the oil when it’s hot, it will pour out of the engine rapidly. Too-quick oil draining can result in old, dirty oil remaining in the engine rather than getting fully removed.
b. Oil Viscosity Suffers
Hot, thin oil also has a lower viscosity than cooled oil. Viscosity refers to the oil’s resistance to flow. Lower viscosity from high temperatures means the oil isn’t as sticky or thick. This can lead to inadequate lubrication between engine components, increased friction, potential wear and tear, and even engine damage over time. That’s why you should always wait for the oil to cool and return to the proper viscosity before adding new oil.
How Long to Wait Before Changing Oil?
The general recommendation from most automakers is to wait at least 2-3 hours after turning off the engine before draining the old oil and adding new. This allows sufficient time for the oil to cool back down to around room temperature and return to its regular operating viscosity.
For vehicles with larger engines that generate more heat like trucks, SUVs, performance cars, etc., it’s best to wait even longer – between 5-6 hours or more. Larger engines retain more heat, so require extended cooling times.
The outside air temperature also affects the cooling rate. On a 50-60°F day, the engine will take less time to reach an optimal temp than if it’s 90°F+ outside. After prolonged highway driving, the engine also stays warmer longer compared to shorter trips. Checking your owner’s manual to follow the recommended cool-down period is wise.
Techniques for Faster Cooling
If you need to change your oil but don’t have half a day to spare, here are some tips to help your engine cool faster:
- Turn off the engine and avoid restarting – Every restart resets the cooling clock.
- Pop the hood open – This allows for maximum airflow over the engine and better heat dissipation.
- Park in a shaded area – Direct sunlight keeps the engine warmer.
- Wait longer on warm days – Cooler ambient temps speed up cooling.
- Let extra time after highway driving – Sustained high speeds mean more retained heat.
- Check oil temperature – The dipstick oil should be room temp before adding new oil.
- Touch the engine – Components should be cool enough to touch barehanded before oil draining.
- Refer to your manual – Follow the automaker’s recommended cooling times.
- Don’t rush it – An extra hour or two is worth it for proper oil viscosity.
Safety Tips for Oil Changes
Changing your engine oil requires working with hot, slippery oil, so safety should be top of mind:
- Use jack stands – Don’t just rely on a jack to avoid being crushed if the car slips.
- Wear eye protection – Safety glasses prevent hot splashes if oil sprays out.
- Use gloves – This protects your hands from hot engine parts and oil.
- Wear old clothes – Oil could splatter onto your clothes, so dress accordingly.
- Ventilate your workspace – Work outside or in a well-ventilated area.
- Tighten the drain plug – Use a torque wrench and don’t overtighten.
- Dispose oil properly – Never dump down drains. Recycle it at auto stores instead.
- Check for leaks – Run the engine after the oil change and look for any new drips or leaks.
Choosing the Right Motor Oil
Not all oils are created equal in terms of engine protection and performance. The type and weight of oil varies by vehicle, so check your owner’s manual for the specific oil recommendation. Some guidelines:
- Synthetic or conventional – Synthetic generally provides better protection.
- Viscosity grade – This measures oil thickness. Common grades are 5W-20 or 5W-30 for most vehicles.
- Ratings – Look for oils that meet API SN Plus or SP rating for newer engines.
- Brand – Stick with major brands like Valvoline, Pennzoil, Mobil 1, Castrol, and others versus no-name oils.
- Mileage – Use higher-mileage oil if your car has more than 75k miles. The extra additives help reduce wear.
Preparing for an Oil Change
To make sure your oil change goes smoothly, prepare all the necessary items ahead of time while you wait for the engine to cool:
- Socket wrench and socket for the drain plug
- Oil filter wrench if needed
- A suitable oil drain pan to catch old oil
- Oil filter and amount of new oil needed per your manual
- A clean funnel to pour in new oil
- Rags or shop towels for spills and messes
- Trash bags for old oil disposal
- A way to get rid of old oil – most auto parts stores accept it
Also, review the oil change steps for your particular vehicle. Cars with oil filters in hard to reach spots or multiple filters require extra attention. And top off fluids like coolant or transmission fluid if needed.
Resetting Service Reminders
Don’t forget to reset your oil change sticker or service reminder light after the oil change. Make note of the current mileage and date so you know when your next oil change is due. Most vehicles should have the oil changed every 5,000-7,500 miles or 6-12 months. Severe duty schedules are even more frequent. Follow your automaker’s recommendations for optimal lubrication and engine longevity.
Your engine requires clean oil at the right temperature to properly lubricate internal components and prevent excessive wear and tear. That’s why letting the engine cool completely before either draining old oil or adding new oil is so important. Waiting at least 2-3 hours, or longer for bigger engines, allows the oil to return to its normal viscosity. Rushing an oil change risks old oil remaining behind or fresh oil not flowing properly. Patience pays off when it comes to proper oil changes!
Follow the tips in this article for safe, effective engine cooling and oil changes. And be sure to check your owner’s manual for the recommended cooling times and oil specifications for your particular vehicle. With a little planning and TLC, your engine will stay lubricated and running smoothly for many more miles down the road.
Ensuring optimal car care involves not only knowing how to change car engine oil at home but also understanding the importance of timing. When contemplating how long to let the engine cool before adding oil, it’s a crucial step in the DIY oil change process.
In our comprehensive guide on ‘How To Change Car Engine Oil At Home,’ we delve into the step-by-step process, providing valuable insights to keep your vehicle running smoothly. Learn the right intervals and methods for a seamless and effective car maintenance routine.”