Changing the oil every 3,000 miles is the easiest way to maintain your Lexus RX300. Changing the oil yourself will cost around $15 to $20 compared to around $40 at the Lexus dealership or an auto mechanics. You can change the oil in your own garage with everyday tools and products you can buy at your local auto parts store.
Slide underneath the car with an oil pan and your socket wrench. Locate a panel underneath the engine with multiple bolts on it.
Unscrew the bolts on the panel and completely remove the panel, so you have access to the drain plug.
Unscrew the drain plug on the side of the oil tank with a socket wrench. Have an oil pan ready to the side of the drain plug to collect the oil. The oil will take about three to five minutes to fully drain.
Wipe the excess oil from around the oil tank with a rag, and screw the bolt back on the tank.
Unscrew the oil filter, which is a barrel shaped object that hangs by itself near the oil tank.
Screw in a new oil filter. Reference your owner's manual to find out what kind of oil filter you should use in your Lexus. The oil filter type differs depending on the year of the RX300.
Reattach the panel that you removed in Step 2. Screw in all the bolts. You are now done with all the work under the Lexus.
Open the hood and unscrew the cap off the top of the oil tank. You will see the cap on the large silver engine cover with the Lexus logo on it.
Place a funnel in the hole leading to the oil tank and begin pouring oil into the funnel. Reference your owner's manual to find the correct type of oil and the amount of oil to pour in the tank. Do not overfill the tank. You can buy oil at an auto parts store.
Screw the cap back on the oil tank located on the engine cover, and close the hood.
