See also:

Treadwear indicators
Narrow bars (tread wear bars) that are distributed over the tire tread. If the tire tread is level with the bars, the wear limit of 1/16 in (1.6 mm) has been reached. ...

Checklist before driving off-road
► Engine oil level: check the engine oil and top it up if necessary. The vehicle can only guarantee a smooth supply of oil on steep stretches if there is a sufficient level of engine oil ...

Brake fluid
WARNING Over a period of time, the brake fluid absorbs moisture from the air; this lowers its boiling point. If the boiling point of the brake fluid is too low, vapor pockets may form in the ...