Steering kickback (vibration)-coil spring

STEERING KICKBACK (VIBRATION)-COIL SPRING

Model

Range Rover

Affected vehicles

All coil spring with anti-roll bar derivatives from VIN LH 610295

Date

1994-01-14

Reference

14/01/94

Bulletin text

SUBJECT Steering Kickback (Vibration) Coil Spring Suspension With Anti-Roll Bar

MODEL AFFECTED VEHICLES

All coil spring with anti-roll bar derivatives Range Rover from VIN LH 610295

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 Bulletins 012/93 and 126/93.

NOTE: Radius arm bushes NTC 6860 were introduced coil spring vehicles at VIN LH 633740

NOTE: Front and rear shock absorbers STC 241 and STC 242 were introduced onto coil spring vehicles at VIN LH 639407.

ACTION REQUIRED

In the event of customer concern carry out the procedure detailed below. Please submit a Product Report on vehicles that exhibit steering kickback after VIN LH 639407, (coil spring derivatives only).

PARTS INFORMATION

NTC 6860 Front radius arm bushes. STC 241 Front shock absorbers. STC 242 Rear shock absorbers. RTC 6825 Harmonic damper kit.

PROCEDURE

In the event of customer concern carry out the preliminary checks 1 to7. (See overleaf)

NOTE: When replacing radius arm front bushes NTC 6781 with NTC 6860 the harmonic damper kit must also be fitted. (Note NTC 6860 have been fitted as standard on all coil spring vehicles since VIN LH 633740). If the vibration still exists on vehicles fitted with radius arm bushes NTC 6860, fit the shock absorber kits.

Note, these shock absorbers were fitted to vehicles at VIN LH 639407.

Continued on following page....

14/01/94

57/01/94/EN

WARRANTY

Normal warranty policy and procedure applies.

COMP. CODE

5R1W Front shock absorbers Rear shock absorbers 5R5W

SRO

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.

SUBJECT Steering Kickback (Vibration) Coil Spring Suspension With Anti-Roll Bar

MODEL AFFECTED VEHICLES

All coil spring with anti-roll bar derivatives Range Rover from VIN LH 610295

Procedure 1 (Before any parts replacement)

1) Road test vehicle to confirm customers concerns. 2) Check tyre 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 required. 10) Fit front STC 241 and rear STC 242 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.

14/01/94 57/01/94/EN