The one difference between changing oil in a Toyota Prius and changing it in a conventional gasoline car is that a flap blocks access to the oil tank. The purpose of the flap is to keep the heat in the engine-battery area, which allows more battery use over gasoline use. The flap opens wide, so it helps to elevate the car several inches first. This isn't necessary, but it does allow the oil to empty into a drain pan placed underneath the flap.
Let the engine cool down so the oil isn’t too hot to handle.
Place a jack under one side of the Prius, and use it to raise the car. Place jack stands underneath so you can slide the jack out and use it to jack up the other side equally high. Put wheel chocks on opposite sides of one of the rear wheels to prevent motion that could make the car unstable.
Open the oil access door under the engine. This door will have three pins holding it in place. They aren’t interchangeable, so keep track of which pin goes into which hole. Remove these pins by pulling, and then twisting, with your fingers. The access door opens 90 degrees if you have raised the car high enough off the ground.
Place a drain pan under the drain bolt at the bottom of the oil tank. If the oil access door is in the way and you can’t raise the car any more, you can either hold the pan up to the drain bolt or let the oil make a mess on the access door before pouring off into the pan.
Remove the drain bolt, using a crescent wrench. The oil will pour down into the pan.
Remove the oil filter housing, using a 65 mm oil filter wrench--always change the filter when you change your oil. The filter is a cylinder in the same area, on the passenger side.
Remove the filter by turning it counterclockwise, as well as its gasket (the rubber O-ring that forms a seal between the filter and engine). Coat the new gasket with oil, and put it in place onto the filter. Put the new filter in place and replace the housing.
Screw the drain bolt back in. Don’t forget to include the washer. You may want to replace the washer; it’s called a “crushable” washer and is not meant to last indefinitely.
Open the hood and pour 4.4 quarts of new oil into the oil tank, or enough so the dipstick reads between minimum and maximum. Pour the oil in where you see a black cap on the left side of a silver metal tank. Use a funnel, and don’t overfill, as this reduces gas mileage, defeating the purpose for getting a Prius in the first place.
Run the car for five minutes. Check to see if the oil drain bolt is leaking.
Turn off the engine and close the oil access door, placing the pins in the holes they each came from.
Lower the car, and properly dispose of the old oil and filter.
