Wheel and tire sizes (Fiesta 4)

The relatively small contact area of the tyres with the road surface must keep the Fiesta on the desired trajectory, regardless of the weather conditions and the state of the road surface. In addition to the forces acting on the tyres when accelerating and braking, there are also centrifugal forces that arise when cornering, which try to move the car in the opposite direction to the turn. In all cases, the tyres must withstand the loads acting on them and ensure that the trajectory of movement is maintained. Under normal load, the radial tyres of the front drive wheels of the Fiesta last approximately 20,000–40,000 km, the tyres of the rear wheels approximately 35,000–60,000 km. Even if you rarely use the car, the tyres should be changed after 7–8 years. During this time, dirt, aggressive environmental influences, internal processes and, last but not least, the sun destroy the tyres to such an extent that they can no longer be used. The appearance of an old spare tire is also deceptive: it cannot be used either, despite the fact that it looks like new.

The sizes of tires installed on Fiesta vehicles are given in Table 13.1.

Two versions of Fiesta car wheels

Ford equips its vehicles with two main types of wheels: steel or aluminium wheels, depending on the equipment and model. On models produced since 1996, the steel wheel sizes vary from 5Jx13 inches to 5Jx14 inches. Aluminium wheels are supplied in the same size for all models. Table 13.1 shows the wheel sizes that Ford provides as standard or additional equipment for various vehicle models. The sizes of tyres and wheels permitted for your Fiesta are specified in the technical passport. If you wish to equip your vehicle with other tyres, consult a service centre.





TECHNICAL DICTIONARY

Wheel size

The wheel is designated by the main dimensions of the rim in inches. In the 5Jx13 marking (in inches), the first digit is the rim width, the letter "J" means the rim profile shape (with a deep base), the last digits are the wheel mounting diameter (13 inches). Features of rims with a deep base: to ensure that the tires fit well, a projection is provided on the seat shelf (shoulder) of the rim located around the entire circumference. When driving fast in a turn, it prevents the edge of the tire from jumping off the seat shelf (shoulder) at the base of the rim.

The text is available on the specified website info portal: FordBook.ru