Brake pads, and how long they really last

A worn pad is not a matter of mileage but of the metal left on it.

Choosing a cabin filter for a diesel

Carbon layers cost more and do a different job from the paper ones.

Why a wiper blade streaks in one direction

The rubber takes a set, and the arm's spring is usually innocent.

Spark plugs and the gap nobody measures

A new plug is not always gapped for the engine it is going into.

Oil filters that bypass under load

The valve opens at a pressure the box never prints on the outside.