How do I change my oil and filter?

Checking your car's engine oil is not one of life's great challenges, but draining the oil and fitting a new oil filter is not something to be undertaken by tech newbies.

Sure, if you're confident you know which end of a socket spanner to hold, you're on speaking terms with occupational health and safety measures and you know where to find the sump plug, knock yourself out.

Hopefully you'll have not only that socket spanner but also a socket to fit the sump plug through which the oil drains. Change the oil in accordance with the manufacturer's recommendations published in the vehicle's logbook. Ensure that you've purchased the right grade of oil for the job.

Important safety point here: You will have to get under the car to loosen the sump plug. Make sure you have a set of hard-wearing overalls.

Also make certain, as a matter of safety, that the car is raised securely on wheel ramps or jack stands, the parking brake is on and the rear wheels are chocked (with bricks or blocks of wood, failing steel chocks from an aftermarket retailer) to ensure the vehicle won't roll back or fall while you're underneath. Don't try any of this on a surface that is less than flat and level.

Place a pan under the sump plug and unscrew the plug (it resembles a wide-headed bolt at the lowest point of the engine). Don't confuse this with the plug for the transmission oil, which will likely be located further back from the front of a rear-wheel drive car or either side of the sump for a front-wheel drive. The plug unscrews anti-clockwise. Set up your socket spanner to unscrew before you climb under the vehicle.

Leave the oil to drain for a few minutes and then replace the plug. Manufacturers frequently recommend replacing the washer that comes with the plug at the same time. Check with your dealer on that point.

Open the oil filler cap on the engine's cam cover and fill the 'crankcase' to capacity, as per the amount specified in the logbook. This can be typically five to seven litres. Check the oil level from the dipstick, just in case you've got the capacity wrong. Don't forget to refasten the oil filler cap.

If you're planning to replace the oil filter, don't refill the oil first. Look for a cylindrical protuberance on the side of the engine block (low down, below spark plugs and manifolds).

There are oil filter wrenches that can be purchased cheaply through automotive parts and tool suppliers, but you can also hammer a screw driver through the thin wall of the filter and use the screwdriver, capstan-style, as a key to unscrew the filter.

Since the old filter is to be disposed anyway, it doesn't matter if you damage it during the removal process. Unscrew the filter anti-clockwise to remove it.

A new filter needs a light smearing of oil on the gasket. Dab your finger in the waste oil from the drain pan beneath the engine and finger-paint the gasket before screwing it (clockwise turning) into place on the engine block. The filter only needs to be tightened enough (by hand) to prevent oil leaking out. It does not need to be tightened with the filter wrench.

Fill the sump to capacity, based on the manufacturer's recommendations in the owner's manual for the vehicle. The manual will provide two capacities, one not including the oil filter volume. If you've replaced the oil filter, you should pour in enough oil by volume to match the larger capacity.

After the refill, check the oil is at the correct capacity using the dipstick. Add a small quantity if the capacity remains below the minimum-fill striation on the dipstick. Before letting the car down, check for any leak from the sump plug and tighten if necessary.