Change Car Oil Filter
The oil filter traps the metal particles and soot suspended in the engine oil. Replacing it at every oil change is essential to preserve the life of the engine: a clogged filter lets unfiltered oil through via a bypass, speeding up wear of the engine components.
Why change the filter at every oil change?
Engine oil gradually picks up tiny metal particles and combustion residues. The oil filter traps them. If it is not replaced, it eventually clogs: the oil then bypasses the filter and circulates unfiltered, accelerating engine wear.
How often should you change the oil filter?
The oil filter should be replaced at every oil change, that is every year or every two years, and at most every 20,000 to 30,000 km. In severe use, shorten this interval. Refer to your vehicle's service book.
Doing the oil and filter change yourself
Difficulty 2/5
Technically accessible but needs a filter wrench (cap or strap type), a torque wrench and a drain pan. Allow around 30 minutes.
Removal precautions
Wear nitrile gloves: the oil can be very hot. Place the drain pan under the filter before unscrewing it to avoid spills.
Tightening on refitting
Screw the filter on by hand until the seal contacts its seat, then tighten a further 3/4 of a turn, or to the torque specified by the manufacturer. Never use the strap wrench to tighten.
Price
From £6 to £15 from a motor factor. Average garage price for the filter alone: around £19. Avoid cheap filters of unknown origin.
Types of oil filter
Spin-on filter
A disposable metal canister that screws straight onto the engine block. Simple to replace: unscrew the old one, screw on the new one. The most common type on older and mid-range vehicles.
Cartridge (insert) filter
A paper filter element housed in a permanent canister. Only the element is replaced. More environmentally friendly (less metal waste) and increasingly common on recent vehicles. Sometimes needs a special tool to open the housing.
