Free play refers to the free rotation of the steering wheel before the road wheels start to rotate. As with free play being built into a steering system by design, excessive free play is something that needs to be addressed as soon as possible due to safety implications.
What Free Play Actually Is
Turn the steering wheel slowly from left to right. Feel for when the wheels start to rotate. The distance between where you first started turning the wheel and when the wheels began to rotate is known as free play. This free play is designed to reduce the amount of slack in the system to compensate for road surface irregularities.
How Much Is Acceptable
Up to 25-30mm of wheel rim movement is generally acceptable on older recirculating-ball steering set-ups. Check for excessive free play by sitting in the car and holding the steering wheel gently between your hands. Gently rock the wheel from side to side and check for any excessive movement before feeling any resistance.
What Causes Excessive Play
The worm gear inside the unit is prone to wear and is often the cause of excessive free play. The adjuster screw, which is located on top of the Steering Box, is also frequently responsible for increasing free play. This is usually a simple matter of tightening the adjuster screw in small quantities (about 1/4 turn at a time) and checking the free play until it is within the specified limits. Other components, such as worn track rod ends or worn ball joints, can also cause excessive free play. Steering Box is covered in more detail at https://westernpowersteering.co.uk/steering-parts/box/.
What Happens If You Ignore It
As free play increases, the steering system’s response becomes progressively worse and can degenerate very quickly. Eventually, the only course of action will be to restore the whole lot.
A slight amount of free play is acceptable but if it feels more than that, have it checked out before it affects your handling of the car.
