Steering: Description and Operation

Power Steering
The vehicle uses a rack and pinion type, variable ratio steering gear with speed proportional Servotronic. The power steering pump is belt driven on all model variants and the power steering oil cooler is of a tube and fin type and is mounted to the front of the cooling pack.

A variable steering rack ratio reduces the amount of turns from lock to lock to improve parking maneuvers without loosing any steering feel at higher speeds.

The steering assistance decreases smoothly at a calibrated rate to increase the steering efforts required as vehicle speed increases. The steering efforts are controlled by the actuator position, which in turn is controlled electronically by the speed proportional Servotronic curve which is incorporated within the Generic Electronic Module (GEM).

Absolute cleanliness must be observed when replenishing the fluid or dismantling any part of the system. A new power steering reservoir must be fitted if the steering gear, pump or fluid cooler is to be replaced. New fluid from a sealed container must be used.


The content of this article/image reflects the changes identified in TSB-ST211-006



1. Replace the power steering reservoir only if any of the following conditions apply:

Reservoir bottle housing is split

Reservoir bottle port is crushed

Fluid is grossly contaminated with particulate matter, witch may or may not result
in a loss of function from the power steering system.

2. If particulate contamination is observed, but the steering system functions
normally, drain the fluid from the system, replace the reservoir, and flush the steering system completely with fresh fluid.