Steering Gear: Service and Repair
Removing and installing steering gear
Removing
- Lift vehicle.
Note!
^ Fix steering wheel with wheels in straight-ahead position (engage steering column lock or clamp steering wheel in centre position with steering wheel holder)! If this is not done, the airbag contact unit will have to be put in centre position after installation of the steering gear!
^ Before feed and return lines are loosened, place suitable container underneath to collect steering fluid.
^ Wear protective goggles and gloves.
1. Remove outermost tie rod ends with press-out tool T10187. When pressing out, screw fastening nut on flush (protects the ball joint thread).
2. Remove -fastening screws- from heat insulation plate (steering transmission/steering shaft). If it is a Cayenne with Servotronic, pull off connector.
3. Remove fastening screw of -universal joint of steering shaft (Arrow)- (push universal joint slightly upwards).
4. Release rear securing mechanism of front axle drive (right-hand side of vehicle). Lift -front axle drive with a suitable lift- (use wooden block or rubber base in order to prevent slipping. Take out fastening screw and lift front axle drive only to the extent that bearing eye above front axle carrier is accessible (when doing so, do not push cardan shaft as far as it will go).
5. Re-insert -fastening screw (Arrow)- (easier to access). Transmission remains in the raised position and lift can be removed.
1. Release -feed and return lines (arrows)- (collect steering fluid in a suitable container). Close lines and open taps with suitable plugs.
2. Remove -fastening screws of steering transmission (arrows)-.
3. Unclip -coolant hoses- from holders to facilitate removal of steering transmission and pull up (steering transmission illustrated transparently here).
4. Remove heat insulation plate and push -steering transmission- towards the right out of the suspension subframe mounting points and turn towards the rear.
5. Turn -steering transmission- backwards by about 90-100 degrees.
6. Carefully pull out -steering transmission- through the left wheel well.
Installing
Warning! Danger of injury and damage to property due to malfunctions in the PSM control range if the steering angle sensor is not calibrated or is calibrated incorrectly!
^ Calibrate steering angle sensor with wheels in straight-ahead position with the Porsche System Tester!
^ If steering wheel has been removed, ensure that airbag spiral spring is in centred position!
Note!
^ When topping up or filling in Pentosin, make sure that it does not come into contact with the coolant hoses! Observe the specifications in order to avoid overfilling and thus overflowing!
^ If coolant hoses come into contact with Pentosin, thoroughly clean them with water IMMEDIATELY!
^ Replace visibly swollen coolant hoses!
^ After fitting the pressure lines, fill steering hydraulics with Pentosin CHF 11 S and bleed steering system.
^ Replace all expansion screws and fastening nuts.
^ Tighten all screw connections with the prescribed tightening torque values.
^ Check and/or adjust toe-in.
^ Calibrate steering-angle sensor.
Installation instructions
Install in reverse order.
^ Replace fastening screw of steering shaft whenever it has been removed. Ensure it is fitted correctly. Insert fastening screw (in correct position, not from the threaded side).
^ Push on universal joint (steering shaft) in correct position, with steering gear and steering wheel or airbag contact unit (spiral spring) in centre position. When doing this, only place steering transmission screws in position (to facilitate assembly when pushing universal joint on). After fastening screws of steering have been tightened, push universal joint on as far as it will go. When fitted correctly and tension-free, universal joint must be at a maximum -distance (arrows)- of 4 mm from the outermost edge of steering transmission dust bellows.
^ Replace steering transmission fastening screws.
^ Screw threads must be clean and free of grease.
^ Ensure that no damage (scoring or similar damage) is caused to the steering rack.
^ If the tie rods are to be reused, remove them from removed steering transmission and fit them on new steering transmission. Insert -new sealing rings (Arrow)- on steering transmission.
Note!
^ The left-hand clamping washer of joint boot must be clamped in such a way that the clamping washer lug forms one line with the steering pinion!
^ The left-hand clamping washer of joint boot must be clamped in such a way that the clamping washer lug faces the direction of the journey horizontally with front axle carrier (suspension subframe)!
^ Failure to do this can result in narrow passages on the left-hand side in the vicinity of the feed and return lines and on the right-hand side in the vicinity of the heat insulation plate!
^ Fit joint boot (not in twisted condition) and secure with -new clamping washers- (Use pliers for clamping washers 74).
^ Check that joint boot is not worn (cracks, slots) and that sealing surfaces are clean.
^ When fitting the ball joints, ensure that the bevel pinions are clean! Remove dirt or grease on bevel pinions, e.g. with a lint-free cloth. Do not use cleaning agent/solvent.
^ Observe airbag safety instructions
^ Fit driver airbag unit
^ Observe notes on steering-gear centre position in the section describing front track adjustment
^ Steering-angle sensor calibrations