Steering — General Information (BMW X5 E53)

The steering system is designed to change the direction of the vehicle's movement, and includes a steering column, steering wheel, and steering mechanism (rack and pinion system) with power steering. Depending on the year of manufacture and configuration, the vehicle was equipped with two types of power steering - a steering mechanism with constant power (basic configuration) or with variable gain (additional equipment). The steering gear is located on the car body and is connected to the ball joints of the wheel hubs. The steering rod ends are made variable in length, which allows you to adjust the angle of the wheels. The steering with a toothed rack has no gaps and easily moves from stop to stop. It does not require maintenance, but it is necessary to monitor the condition of the protective covers. The required operating pressure in the hydraulic booster system is created by a pump with a belt drive from the engine crankshaft pulley. The belt tension is automatic.

Attention! Welding and straightening work on steering components is strictly prohibited.

The car is equipped with a steering system from ZF (Germany) with the following characteristics:

• overall gear ratio – 17.8;
• number of steering wheel turns between extreme positions – 3.0;
• minimum turning radius at the front bumper point – 6.05 m;
• drive gear turning moment (on the removed steering gear) 360° and turning the steering wheel 1/2 turn in either direction from the center position 0.9–1.1 N·m (0.09–0.11 kgf·m);
• the torque of the drive gear turning beyond the above-mentioned sector is 2.0 N·m (0.2 kgf·m);
• maximum working pressure of the pump when measured in one of the extreme positions of the steering wheel: no more than 120–128 bar (kgf/cm²) with the engine "M54", "M62" and "M57", no more than 122–130 bar (kgf/cm²) with the engine "N62";
• hydraulic system filling capacity – 1.2 l;
• refill oil – ATF Dexron II for automatic transmissions (the grades of oils used are listed below);

Check the oil level when the maintenance indicator lights up. BMW-AG recommends the following brands of oil as the working fluid for the power steering system:

• Castrol TQ Dexron IID-22 765;
• BP Autran LTF;
• Shell Super ATF D-21 666/M-891205;
• Elfmatic G2 Syn D-22 517;
• Esso ATF LDS;
• Texamatic 4291 D-21 914;
• Wintershall ATF Dexron S.

The ZF rack and pinion steering is lubricated for life and does not require periodic maintenance. In case of repair work, the corresponding steering components are coated with grease of the Calypsol SF-3-131-TMM3 type. For climate zones with low temperatures (up to -30°C) of the Calypsol D 4024-OK type. Copper-containing paste of the BMW-81.22.9.400.794 type is used for the contact ring of the horn.

The front axle wheel alignment angles on a BMW X5 must be measured under the vehicle's nominal load, taking into account the rear axle wheel alignment angles:

• full fuel tank 93 l;
• driver's seat 68 kg;
• front passenger seat 68 kg;
• in the center of the rear seat 68 kg:
• in the center of the trunk 21 kg;
• working condition of tire treads;
• corresponding division in tires.

Wheel alignment angles must correspond to:

Front axle

Overall positive wheel alignment is 0°18'±10'.

Wheel alignment (difference between left/right max. 30') – -12'±20'

The angle between the turning radius of the inner and outer wheels:

(difference between left/right max 20')

• when turning the inner wheel at an angle of 20° – 1°35'±30'

Caster Angle: (Difference between left/right max. 30')

• when turning the wheel at an angle of 10° – 6°50'±30'
• when turning the wheel at an angle of 20° – 7°06'±30'

Maximum wheel turning angle:

• inner wheel – 37°06'
• outer wheel – 37°07'

Turning diameter – 12.1 m.

Rear axle

Overall positive wheel alignment – 0°18'±10'

Wheel alignment (difference between left/right max. 30') – -1°50'±20'

Geometric axis of the trajectory of movement – 0°±12'

[The original text can be read on the website: BMWMan.ru]