An oil and filter change is the single most important maintenance task you can perform on your vehicle. Engine oil lubricates moving parts, reduces friction and heat, cleans internal surfaces, and prevents corrosion. Over time it degrades and becomes contaminated, losing its protective properties. Regular changes keep your engine running smoothly and can significantly extend its lifespan.
How Often to Change Your Oil
Service intervals vary between manufacturers and engine types. Most modern petrol engines specify between 10,000 and 15,000 km or 12 months, whichever comes first. Turbocharged engines and diesel engines may have shorter intervals. Severe driving conditions (frequent short trips, dusty environments, towing, or stop-start city driving) may also require more frequent changes. Your workshop manual lists the exact interval and specifies whether it falls under the normal or severe service schedule.
Choosing the Right Oil
Using the correct oil specification is critical. Modern engines are designed around specific oil viscosities and additive packages. A Toyota may require 0W-20 ILSAC GF-6, while a Nissan diesel may need 5W-30 ACEA C3. Using the wrong grade can cause accelerated wear, increased oil consumption, or even void your warranty on newer vehicles. Your workshop manual lists the exact specification, and you should match it precisely – not just the viscosity grade but the performance standard.
Step-by-Step Oil Change Procedure
Warm the engine to operating temperature first. Warm oil flows more freely and carries more contaminants out with it than cold oil. A 5-minute drive is sufficient. Raise the vehicle on jack stands (never rely on a jack alone) and place the oil drain pan under the sump.
Remove the drain plug using the correct size socket or spanner. Let the oil drain completely, which takes 10 to 15 minutes. While it drains, replace the drain plug washer with a new one (most manufacturers specify a new copper or aluminium crush washer each change). Reinstall the drain plug and torque it to specification – typically 30 to 45 Nm, but this varies and over-torquing can strip the sump threads.
Remove the old oil filter. On spin-on filters, use an oil filter wrench to break it loose, then unscrew by hand. On cartridge-type filters (common on European and newer Japanese vehicles), remove the filter housing cap with the correct socket and replace the internal element and O-ring. Apply a thin film of fresh oil to the new filter gasket (spin-on) or O-ring (cartridge) before installation.
Install the new filter. Spin-on filters should be hand-tightened only – typically three-quarters of a turn after the gasket contacts the mounting surface. Cartridge housings have a specific torque value listed in your manual. Fill the engine with the correct quantity of fresh oil through the filler cap. The total capacity with filter change is listed in your workshop manual and is typically between 3.5 and 6.0 litres for most passenger cars.
Start the engine, let it idle for 30 seconds, and check for leaks around the drain plug and filter. Turn off the engine, wait 2 minutes for the oil to settle, then check the level on the dipstick. Top up if necessary to bring it between the minimum and maximum marks.
Disposing of Old Oil
Used engine oil is a hazardous waste and must be disposed of properly. Most auto parts stores and council waste facilities accept used oil for free recycling. Never pour used oil down a drain or into the ground.
Why the Manual Matters
The oil specification, capacity, drain plug torque, and filter housing torque are all engine-specific. Your workshop manual has these details for your exact vehicle. MechanicMate offers PDF workshop manuals for over 960 models at mechanicmate.net/shop.
