How to Change the Oil on a 2003 Ford Ranger

The Ford Ranger was called the best-selling compact pickup in 2003 by Consumer Reports. You can change a Ranger's oil and oil filter yourself, with adequate drainage time and no mileage-robbing overflows. You’ll save on labor costs, but one-time expenses include a specialized oil-filter wrench and something to lift the truck that is more stable than an emergency car jack.

Start the engine, and let it idle until the oil-temperature gauge begins registering. This thins the oil so it drains more completely. Unscrew the engine oil-filler cap, letting air in to help oil drainage. If you’re facing the open hood, the oil filler cap is in the center of the engine.

Slide under the engine, and find the oil-drain bolt. It will be about the lowest point under the engine. Don’t confuse it with the transmission-fluid drain plug. You can tell the difference because the metal around the oil-drain bolt will be hot.

Loosen the drain bolt with a regular crescent wrench. If it won’t budge, use a closed-end wrench. The bolt turns counterclockwise. Slide a drain pan under the drain bolt, then unscrew the bolt all the way.

Find the oil filter underneath the engine. Adjust the oil-filter wrench to grip when turned counterclockwise, if it has such an orientation. Put the oil-filter wrench on the oil filter. Turn the wrench, preferably with a socket wrench, although a crescent wrench works, too. You insert the male end of a socket wrench into the hole in the center of the oil-filter wrench.

Unscrew the filter manually. Don’t put your face under it--it’s full of hot oil. Let the oil drain into the oil pan, for an hour if you have the time. This is much longer than repair shops do it, which is one improvement you can make. Screw the drain bolt back in, using a new washer, as recommended by Edmunds. The washer flexes to form a good seal, but this means it wears fast, too. If you have a torque wrench, tighten the bolt to 29 pounds/feet.

Remove the rubber O-ring that seals the filter to the engine. Wipe the area clean with a rag before installing the new seal and then the new filter. Coat the new O-ring with oil first. Screw the filter on until you feel resistance. Adjust the oil-filter wrench to grip when turned clockwise. Use it to turn the filter an additional two-thirds of a revolution.

Add 4 quarts of oil for the Ranger's 2.3-liter engine, 4.5 quarts for the 3.0-liter engine and 5 quarts for the 4.0-liter engine, as recommended by Ford. Pour the oil into the fill hole on top of the engine. Screw the cap back on. Idle the engine until the oil-temperature gauge begins registering. Check any leaks around the drain bolt or the filter.