Every 3,000 to 5,000 miles, you want to change the oil and filter on your vehicle, to flush out any contaminants in the engine and keep everything running smoothly. In the case of the Ford 4.0l SOHC engine found in many Ford Explorers, this is particularly essential, as the engines don't have a good track record for reliability. In this case, the project vehicle is a 2002 Ford Explorer; however, the process is similar for other 4.0l SOHC-equipped vehicles, as well.
Raise up the front of the vehicle using the jack and set it on the jack stands. Make sure that the vehicle is solidly on the stands before crawling underneath it.
Place the drain pan underneath the oil pan on the engine and locate the drain plug. Unbolt the plug using the 3/8-inch ratchet and socket, and allow the oil to drain into the pan. Once the oil is emptied from the engine, reinstall the drain plug using the ratchet.
Move the drain pan underneath the oil filter and use the oil filter wrench to remove the oil filter from the engine. Oil will spill out from the engine at this point, so make sure that you're careful as you lower the filter. Place the filter face down, so that the oil inside it drains into the pan, as well.
Open up the container for the replacement filter and fill the filter with as much 5W-30 motor oil as it will contain. Dip your finger in the oil, and run it around the rubber seal on the outside of the filter--this will create a solid seal. Next, install the oil filter onto the engine, tightening it with your hand, not using any tool.
Lower the vehicle back onto the ground, using the jack. Pop the hood and open up the oil cap on the valve cover, using your hand. Pour the remainder of the five quarts of motor oil into the engine, then reinstall the oil cap. Start the engine and allow it to run for five minutes to circulate the oil.
