A trailing shoe in a drum brake is pivoted at the end of the shoe facing in the same direction as the rotation of the drum. So on the right-hand side of a car travelling forwards, a shoe facing the front of the car would be trailing if it was pivoted at the top.

A trailing shoe is constantly being forced away from the drum and so offers considerably less braking force than a leading shoe.

A trailing shoe becomes a leading shoe when travelling in reverse.

Tappets or cam followers are small steel components on which the cam lobes act. Tappets must be machined to precise size and must resist wear.

Twin clutch transmission is an alternative name for a dual-clutch transmission (DCT).

Timing refers to the phasing of several events which occur while an engine is running, such as valve opening and closing, and the spark or fuel injection.

If these events do not occur at the right points in the combustion cycle, the engine will not operate efficiently – if at all.

Tachometer in Mercedes-Benz SLS

A tachometer is another name for a rev counter, the instrument which displays engine speed in revolutions per minute.

The tachometer, sometimes abbreviated to tacho, usually has a red line or area indicating the maximum safe engine speed, and may also be marked with optimum engine operation speeds for performance or economy.

The word tachometer comes from the Greek tachy (fast) and metron (measure).

Not to be confused with tachograph.