What is steering backlash, its causes and elimination

Backlash is a free play on the connection of two or more parts of a car. Permissible backlash is the maximum amount of displacement, which is not critical for the controlled element.

This phenomenon may occur in:

• steering;
• cardan drives;
• elements of the chassis;
• suspension nodes.

We will deal with the causes of freewheeling in the steering column. Then - how to fix it.

What is steering play

The steering column is the first node in which increased free play may appear. Its main part is a rod fixed on a shaft with hinges.

The connection of these elements is provided by gearing. Even from the factory, there is a slight gap in it. It is necessary so that the edges of the teeth do not wear out prematurely due to friction.

The driver can notice this phenomenon by turning the steering wheel left and right, so that the direction of the wheels does not change. During operation of the machine, the free play on the joints increases. Most often this happens due to the natural wear of the parts.

How the car steering works - see video review:

Causes of backlash

Backlash in the steering appears due to wear of the working surfaces in the bearing, in the bushing, on the bipod shaft, in the T-slot, in the head of the adjustment screw. In addition to the increased free play of the steering wheel, wear of such parts leads to knocking, vibrations, which affects comfort and safety while driving.

Most often, the first assembly to show wear is the connection between the roller and the worm. Due to the axial displacement of the worm when turning the steering wheel at high speed, the car can lose control and get into an accident.

In addition to the natural wear and tear of contact parts, it is mainly the poor condition of the roads that leads to wear in the steering. Although the main load when driving on such roads falls on the car's suspension, but the steering mechanism also gets some part. Also, bad quality rubber is associated with such malfunctions.

Loosening the nut

Although most of the reasons for the appearance of backlash are associated with a breakdown or wear of some unit, sometimes this effect appears for rather trivial reasons. An example of this is loosening the steering wheel nut.

In older cars, to eliminate this effect, it is enough to remove the decorative part of the steering wheel and tighten the nut. If the car uses an airbag installed in the steering wheel, then it must be properly deactivated so that it does not pop (for this, the battery must be disconnected).

Worn rod ends

One of the most dangerous wear in steering is tie rod end wear. These parts are constantly subjected to a serious load, and they are operated in an aggressive environment (constant water and dirt, and in winter also reagents for roads).

Due to constant loads and aggressive action, the liners of the ball bearings, which over time will make the car uncontrollable (the tip falls apart, and the wheels turn sharply in different directions, most often this happens when cornering).

In addition to these reasons, steering play can be associated with:

• A collapsed wheel bearing;
• Incorrect tightening of the steering wheel nut or adjusting rods;
• Wear of ball joints;
• Wear of the cardan drive joints (it is used not only in the transmission of a car);
• Increased clearance of the strap and gears or with their wear;
• Incorrectly selected hydraulic oil.

Signs of breakage

The natural wear of gear joints and articulated gears is slow, so it’s hard for the driver to notice at what point the play began to increase. To control this process, the motorist should periodically check this parameter. So, for cars, the norm is when the free wheeling does not exceed 10 degrees.

When, while driving, the car slowed down the response to the steering wheel turn, the driver needs to stop and check what is the reason. This is a clear sign of damage.

Any creaks, knocks, vibrations, an arbitrary deviation of the machine from a given trajectory - all these are signs of a steering malfunction. Because of this, in an emergency, the driver may not be able to cope with the management of the vehicle and create an accident.

Steering wheel play

Fearing this, some motorists generally try to eliminate the free wheeling of the steering wheel. However, this will accelerate the wear of parts and they will need to be replaced with new ones more often than usual.

In the manual for the operation and repair of the vehicle, the manufacturer indicates the permitted steering clearance. If these data are not available, you should proceed from the basic requirements prescribed in the SDA.

The machine must meet the following requirements:

Car type:	Maximum allowable play (in degrees)
Passenger	10
Cargo	25
Bus	20

As you can see, the larger the dimensions of the car, the higher the amount of free wheeling of the steering.

How to check steering clearance

Check the steering backlash as follows.

• Place the vehicle on a firm, level surface — concrete or asphalt. The wheels of the car are dry, clean and set in the direction of the longitudinal axis of the body.
• Before measuring, the steering wheel is turned left and right to feel the moment when the wheels begin to change their direction.
• A device is installed on the steering wheel that shows the degree of deviation from the center point.
• Indicators of free rotation to the left and to the right are summarized.

What tool is checked

The easiest way to measure steering clearance is by using a standard ruler. A mark is placed on the steering wheel. Then it is turned to the right, the ruler is substituted with a scale to the mark, and with one edge it rests on the left rack. With a free turn to the left, the mark will go through several divisions on the scale. It is worth noting that this method is not accurate for passing vehicle inspection.

Here is another way to determine the total backlash:

How to check the steering backlash yourself

To accurately determine the amount of backlash, you need to purchase a backlash meter. There are two types of these devices: electronic and mechanical. The former are more accurate, can have multiple functions and are very easy to use. The second category does not need batteries, and they are highly reliable.

Here's how the electronic model works:

How to check the steering backlash with the ISL-M

Possible causes of backlash and their diagnosis

In addition to the natural wear of parts, the cause of the appearance of free wheeling in the steering column is a consequence of the malfunctioning of the parts involved in driving the car. All breakdowns can be diagnosed in the following three ways.

With the engine off

If the increased free wheeling is felt when the engine is off, you must check the entire steering scheme. Here are the main problems that diagnostics can identify:

• steering tips worn out;
• breakage of a cross of a shaft of a steering rack;
• development of rack gear teeth;
• if the car is equipped with a steering gear (old cars in which it acts as a power steering), then play can appear in its mechanism;
• wear of the upper or lower ball joint.

When moving

If the steering wheel is loose during movement, attention must be paid to the associated problems.

• The car leads to the side. The reason is not adjusted wheel alignment.
• When turning the steering wheel, extraneous noise occurs. The reason is the lack of power steering fluid.
• A knock at the front when driving on rough roads. The reason is the failure of the steering rods and their tips. If this knock gives into the steering wheel - you need to check the steering rack.
• Steering wheel vibration. It occurs when the wheels are unbalanced. In addition, the cause of the beating of the steering wheel may be a breakdown of the ball bearings or steering tips.
• Loss of ride. Turning the steering wheel with jerks indicates wear on the steering rack.

When braking

Steering wheel free play during braking may indicate the following problems:

• failure of the hub bearing. This breakdown can be detected by lifting the car on the jack and swaying the wheel. If it plays, this means a problem in the wheel bearing.
• after a recent repair, the chassis mechanics did not tighten the hub fastening;
• poorly tightened steering mounting bolts;
• wear of brake discs or pads.

Any changes in the behavior of the car on the road are worthy of close attention of the motorist. Ignoring alarms is fraught not only with the failure of parts, but also with the creation of an emergency.

How to eliminate backlash

In many cases, steering wheel play can be eliminated by properly adjusting the vehicle's control system. It is worth checking the tightness of all fixing bolts, as well as paying attention to the adjusting screws. How to remove steering backlash in difficult situations?

In the steering column

Cardan joints are fixed on the steering shaft. There are two in standard columns. They are fixed with bolts. Another reason for the free wheeling in the steering column is the development in the sockets where these elements are installed.

To carry out repairs, you will need to put the car on a flyover or drive it into a garage with a viewing hole. When replacing the spider, the steering wheel should be locked. If the driver hears rattles after replacing the hinge, tighten the mounting bolts.

The clearance in the steering gearbox (if it is present in the car) is eliminated by adjusting the clearance between the bipod shaft and the worm shaft.

Steering wheel

Rarely, but it happens that a complete replacement of all worn parts does not eliminate the increased free play. In this case, check the installation of the steering wheel itself. In some cars, the gear mount of this part fails due to the poor-quality material from which it is made.

So, eliminating backlash in the car’s control system is not just a matter of comfort. The safety of all who are in the car depends on the health of its elements.

Here's another helpful tip on tuning your steering:

How to TIGHTEN the steering rack with power steering? Should I REPAIR it?

Consequences of driving with large backlash

If the driver ignores the gradually increasing backlash of the steering for a long time (and this happens almost imperceptibly), then over time the car will stop responding in a timely manner to the driver's actions - belated turning of the wheels with a large eversion of the steering wheel. At low speed, you can control the car, although such a ride can not be called comfortable, especially when the car is moving on a track - the transport will constantly need to be "caught", as it will always try to change its trajectory.

But high speed and a large backlash of the steering wheel will sooner or later lead to an accident, especially if the car is moving in heavy traffic. The driver can easily lose control of the vehicle when the steering wheels hit a hole or any unevenness.

Every driver needs to keep an eye on the steering rack angle. It will not be difficult for an experienced motorist to notice, but for an inexperienced it is much more difficult to do it. To facilitate this task, special equipment has been developed, which is available in many car services.

Repair cost to eliminate backlash in steering

For personal use, there is no reason to buy such equipment. The cost of the luftomer itself varies between 400-800 dollars, and you will not have to use the equipment so often, therefore it is economically unjustified to purchase a device to diagnose your car.

As for the parts themselves, their cost is for:

• Bearing - more than 12 cu;
• Nut retainer - from 16 cu;
• Steering rack stem - above $ 50;
• Tie rod joint - more than $ 16

Of course, the price of parts depends on the supplier, the policy of the auto parts company, and the car model. The client will have to pay at least $ 20 for the work. Of course, this also depends on the price list of a particular service station.

What is meant by total steering wheel play?

Often, experts use the expression "total backlash" in relation to the backlash in the steering of a car. Let's consider what is meant by this term. In short, this is not a deviation in one direction from the central position of the steering wheel before the moment of impact on the wheels, but an indicator of the maximum deviation from one extreme point to another.

Now a little more detail on how the steering works. The rod, which is included in the transmission of the steering rods, has a clearance of a couple of millimeters. This is necessary so that no wear is formed on the contact surface of the part due to the frictional force under a large load. Thanks to this technological solution, the surface of the teeth does not wear out quickly, and the mechanism has a sufficiently high working life.

Visually, the presence of this gap is determined by the free rotation of the steering wheel until the forces begin to be transmitted to the thrust. This allows the driver to determine when the car is starting to change direction. Some drivers think this is a factory "defect" and try to fix it. But the complete absence of backlash only accelerates the wear of the rod, because of which the part will have to be changed soon.

So, the backlash in the steering wheel should be present. Only this parameter should be within acceptable limits. Moreover, this parameter directly depends on the dimensions of the vehicle: the larger its dimensions, the greater the backlash indicator is allowed in it.

What is the steering wheel start?

When measuring the total steering play, it is necessary to take into account the beginning of the steering wheel rotation. To determine this parameter, you must use special equipment that allows you to recognize the movement of the rudder in one direction or the other by 0.06 degrees.

Visually, this value cannot be determined. For this, the swivel wheels are set to the position of the vehicle's straight-line movement. The angle of deviation from the center point by 0.06 degrees is the beginning of the steering wheel rotation.

Video: eliminating steering play

At the end of the review, we suggest that you familiarize yourself with a small video on how the steering play is eliminated:

Adjusting the steering column vaz or how to remove the backlash on the steering wheel

Conclusion

So, the increased backlash in the steering is fraught with serious problems up to an accident. To prevent such an outcome, it is periodically necessary to carry out diagnostics and, if necessary, repair the steering.

Frequently asked questions and answers:

How to measure steering play. To do this, you need a ruler, bar or wire. Swivel wheels are installed in the straight-line direction of the vehicle. A strap, wire or ruler is inserted with its end to the lower part of the steering wheel (outer side of the rim). Turn the steering wheel until the rack starts to act on the wheels. This will be one extreme point. Here, a mark is made on the rim of the steering wheel. The bar or ruler does not change position, and the steering wheel turns in the opposite direction until the moment of impact on the wheels. Here, too, a label is put. The distance along the rim between the marks should not exceed 4 centimeters. Otherwise, it is necessary to look for the cause and eliminate it.

Steering play at speed. For those who switch to a car with power steering at high speeds, it may seem that the steering wheel is too loose, although in fact there is no backlash. A similar effect has a car that has just been changed for "winter". These tires are softer, and you can also get the impression that the backlash increases at speed. The steering wheel may be level and the car is out of rut (especially if the tires are wide). If backlash of the steering wheel or incorrect operation of the car control appeared after a recent hit in the hole, then it is imperative to check the geometry of all elements of the steering, suspension and chassis.

How to remove the backlash of the steering wheel. This may require tightening the steering rack if this effect is caused by wear of the cushioning materials or loosening of the fasteners to the car body. Also, this malfunction may be due to the development of the intermediate shaft. In this case, the part is changed to a new one.