What happens when you change your own oil

An oil change means draining the old oil from your engine, replacing the oil filter, and filling the engine with fresh oil. When you do it yourself, you remove the drain plug underneath the engine to let the old oil flow out into a pan, unscrew the old filter and screw on a new one, then pour new oil through the filler cap on top of the engine. The whole process takes 30 minutes to an hour for most cars, costs $25 to $75 in materials, and requires only basic tools you may already own.

The main reason people change their own oil is cost. A shop charges $40 to $150 depending on the oil type and your vehicle, while doing it yourself costs roughly half that. The trade-off is that you handle the work, dispose of the old oil yourself, and need to know which oil type and filter your car needs before you start.

Key Takeaways

  • You need your car's owner manual or a parts store lookup to find the correct oil type, oil capacity, and filter part number before you buy anything.
  • The basic tools are a wrench or socket set, an oil filter wrench, a drain pan, and a funnel — most people already own these or can borrow them.
  • The oil drain plug is underneath the engine and requires the car to be safely raised or parked on a slope; working under a car without proper support can cause serious injury.
  • Old oil must be disposed of at a recycling center, auto parts store, or service station — pouring it down a drain or into soil is illegal and damages the environment.
  • The job takes 30 to 60 minutes and you should check the oil level with the dipstick a few minutes after starting the engine to make sure you added the right amount.

Finding the right oil type and filter for your car

Before you buy oil or a filter, you need three pieces of information: the oil viscosity (the thickness rating like 5W-30), the total amount of oil your engine holds, and the filter part number. All three are in your owner's manual in the maintenance section. If you do not have the manual, you can look up your car's year, make, and model on the website of any major auto parts store — they will show you the correct oil and filter.

Oil viscosity matters because using the wrong thickness can damage your engine or cause it to run poorly. The number before the W (like the 5 in 5W-30) describes how the oil flows in cold weather; the number after describes flow at normal operating temperature. Your manual specifies which rating your engine needs. Do not guess or assume that thicker oil is better — follow what the manual says.

Write down the filter part number too. Filters look similar but are sized differently for different engines, and an undersized or oversized filter will not seal properly. The part number is the only reliable way to get the right one.

Gathering tools and materials

You need an oil drain pan (a shallow rectangular pan that holds at least 6 quarts), a wrench or socket set that fits your drain plug, an oil filter wrench (a metal band or cup that grips the filter), a funnel that fits your oil filler cap, and new oil and a new filter. Most people own wrenches and a funnel already. A drain pan costs $5 to $15 new, and an oil filter wrench costs $8 to $20.

You also need a way to safely raise the car or access the underside. If your driveway slopes, you can park on the slope with the drain plug side lower. Otherwise, you need a jack and jack stands — never work under a car supported only by a jack, because a jack can fail and the car can fall on you. If you do not own jack stands, borrow them or have the work done at a shop.

Finally, have rags or paper towels on hand, and know where you will take the old oil to be recycled. Most auto parts stores accept used oil for free, and many service stations do too. Call ahead to confirm.

Draining the old oil safely

Park on level ground or a slope with the drain plug side lower. If you need to raise the car, use a jack to lift it, then place jack stands under the frame on both sides and lower the car onto the stands. Never rely on the jack alone. Put on work gloves and safety glasses.

Locate the drain plug underneath the engine — it is a bolt sticking down from the oil pan. Place your drain pan directly underneath it. Using your wrench or socket, turn the plug counterclockwise to loosen it, then unscrew it by hand the rest of the way. The old oil will flow out; it may still be warm from the engine, so be careful. Let it drain completely, which takes 5 to 10 minutes. Once the flow slows to a drip, wipe the drain plug clean with a rag and set it aside.

While the oil drains, locate the oil filter. It is a cylindrical canister screwed onto the engine block, usually on the side or top. Position your drain pan underneath it to catch the oil still inside. Using your oil filter wrench, turn the filter counterclockwise until it comes free, then unscrew it by hand. Drain any remaining oil into the pan. Wipe the filter mounting surface clean with a rag.

Installing the new filter and adding fresh oil

Before you install the new filter, explore a thin layer of new oil to the rubber gasket (the ring) on the top of the filter. This helps it seal properly. Screw the new filter onto the mounting surface by hand until the gasket touches, then turn it an additional three-quarter turn. Do not use the filter wrench to tighten it — hand-tight is correct. Over-tightening makes it difficult to remove next time and can damage the gasket.

Reinstall the drain plug. Wipe it clean, then screw it back in by hand and tighten it with your wrench. It should be snug but not forced; over-tightening can strip the threads in the oil pan. If you are unsure how tight, your manual usually specifies the torque, but hand-tight plus a quarter turn is a safe standard.

Locate the oil filler cap on top of the engine — it usually has an oil can symbol on it. Unscrew it and set it aside. Place your funnel in the opening and slowly pour in the new oil. Pour in slightly less than the full amount your manual specifies, then stop and check the level with the dipstick.

Checking the oil level and starting the engine

Pull the dipstick out of its tube, wipe it clean on a rag, reinsert it fully, then pull it out again and read the level. The dipstick has marks for minimum and maximum; the oil should be at or just below the maximum mark. If it is below the minimum, add a small amount more and check again. If it is above the maximum, you added too much — use a turkey baster or syringe to remove the excess into your drain pan.

Once the level is correct, reinstall the oil filler cap. Start the engine and let it run for 30 seconds to a minute. The oil pressure light on your dashboard should come on briefly, then turn off as oil circulates through the engine. If the light stays on, turn off the engine when ready and check that the drain plug and filter are tight and not leaking.

Turn off the engine and wait 5 minutes for the oil to settle. Check the level one more time with the dipstick — it may be slightly lower now because oil has filled passages in the engine. Add a small amount if needed. If the level is correct, you are done. Dispose of the old oil at a recycling center or auto parts store.

Lowering the car and cleaning up

If you raised the car with a jack, carefully raise it again just enough to remove the jack stands, then lower it slowly to the ground. Remove the jack stands and store them safely. Do not leave the car on a jack unattended.

Pour the old oil from your drain pan into a sealed container or the recycling container at your parts store. Wipe up any spills with rags or paper towels and dispose of them in the trash. Wash your hands and any tools that touched the oil.

Record the date and mileage of your oil change in your owner's manual or a maintenance log. This helps you track when the next change is due — most cars need an oil change every 5,000 to 10,000 miles depending on the oil type and engine, and your manual specifies the interval for your vehicle.

Frequently Asked Questions

What should I do if I spill oil on my driveway?

Soak it up when ready with rags, paper towels, or cat litter to prevent it from spreading. Once absorbed, dispose of the material in the trash. For large spills, contact your local environmental agency for guidance on cleanup. Never hose oil into storm drains or soil.

Can I reuse the old oil or does it have to be recycled?

Used motor oil can be recycled and refined into new oil or used as fuel, so take it to a recycling center or auto parts store. Do not pour it down a drain, into soil, or into the trash — it is toxic to groundwater and illegal to dispose of that way in most places.

What if the oil filter is stuck and I cannot unscrew it?

Tap the filter wrench gently with a hammer to help it grip, or wrap a rubber band around the filter for extra grip. If it is still stuck, stop and do not force it — forcing can damage the filter housing. Have a shop remove it, or try again after the engine has cooled completely.

How do I know if I added too much oil?

Check the dipstick 5 minutes after starting the engine. If the level is above the maximum mark, use a turkey baster or syringe to remove oil into your drain pan until the level is correct. Overfilled engines can damage seals and cause leaks.

Do I need to change the oil filter every time I change the oil?

Yes, the filter should be replaced with every oil change. A used filter is clogged with contaminants and cannot clean the new oil effectively. Reusing a filter defeats the purpose of changing the oil.