There was a time, not so long ago, when the answer to this title could have been eight words long: ratchet, socket set, and an oil filter wrench. That's it, job done. These days, a simple oil change may seem out of reach of the average home mechanic, requiring everything from a specialized filter wrench to three 17.5 mm hex-end doodad. In reality, it's not quite as bad as all that. It's just that different cars require different tools, and it helps to know what those are ahead of time.
The ratchet, socket set, and oil filter wrench have their place. In most cases, you'll find that the oil change procedure hasn't changed much, with a few additional steps. You'll need a ratchet and socket set to remove the oil drain plug, an oil filter wrench (or maybe just a strong grip) to remove and install the filter, a drain pan to catch the spent oil, and a funnel to refill it. You'll also want to keep a few empty gallon jugs on hand, so you can take the used oil to your local recycling center. Apart from these basic items, you may need a torque wrench to properly install the plug and filter, though most experienced mechanics just tighten the bolt and filter by feel. The general rule is "hand tight," or about as tight as you can get the bolt just turning the ratchet with your wrist. If you are new to changing your oil though, use a torque wrench and the proper factory torque specs. It's easy to over-tighten a bolt and strip the threads if you don't have practice. You might also need ramps or a floor jack, jack stands, and wheel chocks if you have to go under the vehicle.
Variations on the Standard Tools
Many new cars use "splash guards" or "under-trays" that cover the bottom of the engine compartment. These lower covers keep excess water, dirt, and rocks from kicking up into your engine compartment and sometimes improve fuel economy by reducing aerodynamic drag . Depending on your make and model, you may need remove this tray to access the drain plug and filter, and that could require any number of specialized sockets or bits including an Allen-head, Torx, or square-bit screws. Crawl under your vehicle, assess the situation and buy the appropriate bits before starting. Some new vehicles also require an engine-specific oil filter wrench. Volkswagen, for instance, likes to use filter caps that resemble hex-head bolts, which require a large, model-specific, end-cap-style socket. Don't assume your traditional strap- or locking-type filter wrench is going to work without consulting the owner's manual or manufacturer.
The oil pump is more common among German manufacturers like BMW than anyone else. Though it's not impossible to do a traditional oil change on these cars, they're designed to have the oil sucked out with a vacuum pump through the dipstick tube. For this you'll need either a hand-pump or electric oil pump. At first this might seem like an unnecessary aggravation, but you'd be surprised how much easier and cleaner it makes the whole process. It is especially easier if the vehicle has a filter accessible from the top - meaning, you don't even have to crawl under the car to complete the oil change. The oil pump is a tool worth looking into, even if you don't have a car that requires it.
You might need a computer code scanner and reader to reset the Oil Life Monitor system. Many vehicles have some provision in the computer interface to reset the OLM system, but you might find it necessary or simpler to do it with a scanner. They're often available on loan at large chain auto parts stores. You may also need a new oil pan bolt, bolt gasket, or O-ring. Some bolts, gaskets, and O-rings are only designed to be used once and replaced after removal. This is a little more common on vehicles that require an oil pump for changes. In these cases, the drain bolt is may be redundant, and it's not meant to be removed during every service. But if your vehicle requires a new bolt, gasket, or O-ring, do not remove and re-use the old one under any circumstances as it can leak. If you don't know if you should replace these parts, consult your owner's manual, call the dealership, or ask the auto parts store where you buy your supplies.