Steering Wheel - Vibration
14/01/9457/02/94/US
SUBJECT
Steering Kickback (Vibration)
Electronic Air Suspension (EAS)
AFFECTED VEHICLES
Electronic Air Suspension Derivatives
MODEL
Range Rover
DETAIL
Prolonged steering wheel vibration over uneven road surfaces, after crossing a ridge or travelling on a poor condition road surfaces. The resultant action of the steering is that initial sudden steering movement does not cease after the first disturbance but is gradually damped out over a series of steering wheel movements. Typically four in quick succession. The steering wheel movement reduces in severity with each oscillation.
NOTE: This Bulletin replaces the previous Bulletin P93/57-003
NOTE: Radius arm bushes NTC 6860 were introduced onto EAS vehicles at VIN LH 642119
ACTION REQUIRED
In the event of customer concern carry out the procedure detailed below.
PARTS INFORMATION
NTC 6860 Front radius arm bushes.
STC 1473 Front shock absorbers.
STC 1474 Rear shock absorbers.
RTC 6825 Harmonic damper kit.
PROCEDURE
In the event of customer concern carry out the preliminary checks 1 to 7.
NOTE: When replacing radius arm front bushes NTC 6781 with NTC 6860 the harmonic damper kit must also be fitted if not already fitted. (Note NTC 6860 have been fitted as standard on all EAS vehicles since VIN LH 642119). If the vibration still exists on vehicles fitted radius arm bushes NTC 6860, fit shock absorber kits.
WARRANTY
Normal warranty policy and procedure applies.
Claim Type: R
Fault Code: W
Front shock absorbers
Rear shock absorbers
COMP. CODE
N/A
SR0
Procedure 1 only
57.10.30 road test and checks 01.20 hours
Procedure 2 (includes procedure 1 time)
60.31.10 Road test, checks, fit harmonic damper
and front and rear shock absorber kit. 03.45 hours
Procedure 1 (Before any parts replacement)
1) Road test vehicle to confirm customers concerns.
2) Check tire condition and pressures.
3) Check all steering and front suspension fixing torque values. Refer to the Workshop Manual sections 57.60.64.
4) Check and adjust front wheel balance.
5) Check front hub end float. Refer to the Workshop Manual section 54.
6) Check and reset steering box on centre position.
7) Re-assess vehicle, if the original concern still exists proceed as follows:
Procedure 2
8) Replace the front radius arm bushes NTC 6781 with NTC 6860.
9) Fit harmonic damper kit. If not already fitted.
10) Fit front STC 1473 and rear STC 1474 shock absorbers.
11) If it is necessary to adjust front hub pre-loads refer to section 57 of the workshop manual.
NOTE:
Under no circumstances should the swivel pin pre-load be set higher than the recommended settings. Should the pre-load be set higher than that stated premature wear of the bearings will take place and steering feel will be affected. Refer to the Workshop Manual section 54.
Should steering kickback be evident after carrying out these checks, please submit a Product Report to Technical Service.