The common faults occurring in the automobile steering systems are discussed below along with their remedies or troubleshooting technique.
- Excessive Backlash in Steering
The most probable cause of this steering linkage due to wear of ball joints and the steering box. Check these are rectify as required. If the slackness is not present, then the fault may be any of the following.
- Steering gear box be loose in chassis frame which can be tightened.
- Steering drop arm may be loose on splines. The damaged part has to be placed.
- The bearing at the front wheel stub axle or the ball joints may be loose or worn. They should be repaired or replaced as required.
- The adjustment of the steering gear or linkage may not be proper, which may be done correctly.
- Defective shock absorbers which have to be replaced.
- Low power steering fluid (in case of hydraulic power steering), which may be corrected by filling up the steering fluid reservoir.
When the vehicle is being driven straight, it turns slightly to one side and then when the driver turns the steering to bring it back to the straight ahead, it turns slightly to the other side. Thus, the driver has to adjust steering constantly to keep the vehicle direction straight. The defect is called wander. It may be caused due to any one or more of the following:
- Tyres may be badly worn. Install new tyres and check wheel alignment which may require resetting.
- The bearing of steering knuckle may be tight which may be corrected.
- The front wheel bearings may be worn out. If so, the same ought to be replaced.
- The amount of castor on the wheels may be less, which can be increased by putting wedges underneath the suspensions springs.
- The vehicle may be simply overloaded at the rear.
- The toe-in may be incorrect, which can be reset by adjusting tie- rod length.
- The ends of tie rod, the spring U-bolts or the steering gear mountings may be loose, which may be tightened.
- Lack of lubrication in linkage and kingpins. To remedy lubricate and free up any components which are frozen and will not take lubrication.
- Pulling to one side
Sometimes the vehicle constantly pulls towards one side. This may be due to one more of the following causes:
- The tyre pressure may be uneven which should be checked and corrected if necessary. Steering pulls to the side having low air pressure.
- The unevenly worn out tyres may also be source of this trouble which may be replaced.
- Some of the brakes may be dragging, which can be adjusted.
- The camber may have changed due to wearing of bushes or any damage to front suspension. The vehicle pulls to the side of axle having greater camber. The damaged part in such a case has to be replaced and camber readjusted.
- The castor on the front wheels may be uneven or incorrect. The same may be checked and adjusted suitably.
- Alignment of front wheels may e incorrect, which should be adjusted correctly.
- The front wheel bearings may be tight, which may be adjusted as required.
- The suspension spring may be broken, which has to be replaced.
- The stiffness of the front springs may have become uneven with use. The only remedy is to replace both the springs.
- Spring tie bolts may have broken. Replacement is the only solution.
- Defective shock absorbers. The only alternative is to replace them.
- Wheel Wobble (Low speed shimmy)
The oscillation of the front wheels at low speeds is called wheel wobble. This is generally due to dynamic unbalance of the wheel assembly, which may have developed due to following reasons:
- Tyres may have worn unevenly, which should be replaced.
- Incorrect balance weights fitted, which can be refitted correctly.
But apart from these there are other reasons also :
- The tyre pressure may be uneven. The same can be remedied by inflating the tyres to the specified
- The ball joints may have worn out, which should be replaced.
- Steering gear or wheel bearings may be loose which can be adjusted or replaced as required.
- The stiffness of the springs may be less. In such a case either add additional leaf to both the springs or replace them both with stiffer springs.
- The camber may be incorrect or uneven, which may be suitably adjusted.
- The castor may have become excessive due to wear of bushes or damage to front suspension. The damaged parts in such a case have to be replaced.
- High Speed Shimmy
The oscillation of the front wheels at high speed is called high speed shimmy. Apart from the dynamic unbalance, the following factors may cause this trouble:
- Wheel rim may be buckled, which can be straightened or replaced as required.
- Front tyres may be having uneven pressure, which may be inflated correctly.
- The bearings of front wheels may have worn out or otherwise loose. If so, the same have to be replaced.
- Hydraulic shock absorber may be faulty. The only solution in such a case is the replacement.
- The toe-in of front wheels may not be correct, which can be reset.
- Wheel Tramp
Sometimes the front wheels of vehicle at high speeds vibrate so violently that an almost uncontrollable motion of the front portion of the vehicle is caused. That is called wheel tramp and it may be due to any or more of the following reasons:
- The tyre pressure in the wheels may be unequal, which may be checked and reset.
- The wheel assembly may not be balanced dynamically, which should be taken out and balanced.
- The front shock absorber may be defective, which has to be replaced.
- Incorrect castor, which may be checked and reset.
- Excessive Tyre Wear
The probable main reasons for excessive wear of the tyres are given below.
- Tyre pressure may not be correct, which may be checked and corrected if necessary.
- Excessive toe-in or toe-out. These may be checked and reset if necessary.
- Excessive camber, which may have developed due to wear of wheel bearings or some damage to front suspension system. The damaged part should be replaced.
- The brakes may be dragging, which can be readjusted.
- Hard Steering
When the effort required for steering is more than the normal it may be due to any or more of the following reasons:
- Tyre pressure may be too low, which can be tested and corrected if necessary.
- Excessive castor may be there, which should be adjusted properly.
- There may be excessive friction in the steering gear box or linkage or ball joints, which should be lubricated to reduce the friction.
- Steering gear adjusted too tightly or binding condition in steering column. Adjust steering gear and align steering column.
- Incorrect wheel alignment, which may be checked and corrected as required.
- Defective power steering pump, which should be checked for pressure and serviced or replaced as required.
- Loose power steering pump belt which may be checked and adjusted.
- Incorrect power steering fluid level which can be corrected appropriately.
- Slipping Steering
Possible causes for this defect may be:
- Incorrect level of power steering fluid, which can be corrected.
- Defective power steering pump, which can be checked and serviced or replaced as required.
- Power steering belt may be worn, which may be replaced.
- Leaking power steering rack, which may be repaired or replaced as required.
- Damaged steering rack mounts, which must be replaced.
- Poor Returnability
Poor return of the steering wheel to centre may be due to the following reasons:
- Tyre pressure may not be correct. Inflate to the specified value.
- Steering gear to column misalignment. Align the steering column.
- Tight or frozen steering shaft bearings which will have to be replaced.
- Tight steering linkage, which can be lubricated. If required, the defective pivots may be replaced.
- Steering gear may be adjusted too tight. Adjust preload to specifications.
- Front wheel alignment may be incorrect, which can be checked and corrected as necessary.