shock absorbers the hidden danger

a recent national survey of 11,000 cars conducted by monroe and ats found that 23% of vehicles tested had shock absorbers that were either worn or in need of replacement. one in four of cars on britain's roads are in a potentially dangerous condition, and the older the car, the greater the risk.

What is of even more concern is that the majority of car owners are not even aware of the potential dangers. They do not know what shock absorber does, and because it is hidden behind the car's wheel, never think about the need for checking or replacement.

Think about your shock absorbers is the simple message to the motorist - particularly owners of cars that are four years old or more. While your shock absorbers may not need replacing now, have them checked regularly and enjoy the peace of mind that your car is running safely.

The danger of worn shocks

A vehicle's safety relies on having good tyres, brakes and steering. The role of the shock absorber is to keep the car's tyres in permanent contact with the road, helping to provide optimum grip in the wet, when cornering and especially when braking. By being part of the suspension, it also contributes enormously towards ride comfort.

On a car with worn shock absorbers, no matter how efficient the other safety features - tyres and brakes for example - the safety of the vehicle, its occupants and other road users is seriously compromised.


Just as the role of the shock absorber is not generally understood, neither are the affects of worn shocks. These include:

Reduced braking efficiency/ longer braking distances:

A car with 50% worn shocks needs an extra 2.1 metres (6.9ft) to stop when braking from a speed of 50mph in dry conditions.

With just one defective shock absorber, the same car takes 2.6 metres (8.5ft).

Braking on a curved road at 30mph with one rear shock absorber requires a further 2.3 metres (7.5ft) to stop.

Reduced Cornering Ability:

On a tight corner (40metre radius) a car with 50% worn shocks loses grip from the rear wheels at 35mph, compared with 40mph for the same car with new condition shocks.

Greater risk of aquaplaning:

A large car (BMW 520i) with worn shocks starts to aquaplane at 68mph, 10mph earlier than the same car (78mph) with new shocks - a difference of 15%.

Reduction of ABS efficiency:

A medium sized family car (Vauxhall Vectra) with anti-lock brakes (ABS) and with 50% worn shocks, takes a further 6.6metres (21ft) to stop when braking on a snow covered road compared with the same car with good condition shock absorbers.

Other affects of worn shock absorbers include loose, sloppy steering control; increased tyre wear and reduced grip; increased headlight oscillation and the risk of dazzling oncoming traffic at night; driver fatigue and passenger discomfort.

Out of sight, out of mind - the need for regular checking

Shock absorbers are hidden underneath the car's wheel arches, so unlike tyres are not easy to check regularly for visual signs of damage. Once a car has covered some 40,000 miles, most experts recommend checking every 12,000 miles.

Feel no evil.

The performance of a shock absorber deteriorates gradually and imperceptibly over time, during which the driver unwittingly adapts his or her driving to compensate for the wear and worsening condition and handling of the car. Motorists should be aware of this, and have their vehicle road tested annually by a qualified mechanic who can advise accordingly.

Be safe, be sure: don't forget about your car's shock absorbers - have them checked professionally and regularly.