Changing the oil in a 2003 Chevy Silverado is important to properly maintain the vehicle in accordance with the Chevrolet maintenance schedule. When you perform an oil change, old engine oil is drained and refilled and a new oil filter is installed. This ensures that the oil entering the engine is clean, which is important because engine oil provides the only lubrication that keeps bare metal from touching other metal in the engine. An oil change on a 2003 Silverado should be completed when the information computer on the dashboard indicates that service is necessary.
Remove the oil filler cap. The filler cap is located under the hood on the engine’s valve cover. Taking off the cap allows oil to drain from the engine more quickly.
Lift the vehicle using a jack. You should be able to complete a Silverado oil change without using a jack to raise the vehicle. However, if you cannot access the oil pan with the vehicle lowered, raise each front side of the Silverado with a jack before placing jack stands underneath both sides of the front axle.
Remove the oil pan drain plug. The plug is located on the rear of the oil pan, facing the back of the vehicle. As the plug is loosened, oil will begin to shoot out of it, so make sure that a drain pan is placed underneath the drain plug.
Remove the old oil filter. This should be done using a band-type oil filter wrench. Once you break the filter loose, you should be able to finish loosening it by hand. Make sure that the rubber gasket from the old filter is removed from the engine block.
Install the new oil filter. Lubricate the rubber seal on the new filter with clean engine oil. Thread the oil filter on until it is hand tight, and then make it snug by using the oil filter wrench. Don't turn it more than 1/4 turn past finger tight with the wrench, though--overtightening the filter can crimp the flow of oil through it.
Install the oil pan drain plug. Once the new filter is installed, most of the oil should be out of the engine. Reinstall the drain plug, tightening it by hand and making it snug using a ratchet and socket.
Add oil. Depending on whether you have a 4.3 liter, 4.8 liter or 5.3 liter engine, fill the engine oil to the level noted in the owner's manual.
Check for leaks. Briefly start the engine and check for leaks around the drain plug or oil filter. If there are leaks, make sure that the drain plug and filter are threaded properly.
Lower the Silverado. If you placed the Silverado on jack stands to complete the service, lower the truck using a hydraulic jack.
Check oil level. With the truck lowered off the jack stands and on level ground, check the oil level. It should be between the low and full marks on the dipstick. If the oil is below this range, add a little bit of oil and recheck with the dipstick each time you add more oil.
