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Suspension and steeringÖ

The suspension and steering systems on your vehicle make critically important contributions to the safety of your vehicle.  Due to their complexity and the specialist skills required to service them, itís important to have a qualified mechanic who has expertise in these areas to check over your suspension and steering systems every twelve months for proper functioning and safety.  He or she will be able to determine if any parts are worn out (such as shock absorbers) and need to be replaced.  Having said that, it helps to be able to test yourself whether certain components such as shock absorbers are worn out, since youíre the person driving your car everyday.  A simple method of gauging whether the shock absorbers on your vehicle are still functioning correctly is provided below.

Know the condition of your vehicleís shock absorbersÖ

Knowing the condition of the shock absorbers on your vehicle is important because their condition affects how well your vehicle handles, particularly when the roads are wet.  Furthermore, knowing their condition is critically important when embarking on high-speed freeway driving.  Itís important to exercise a lot of care if the shock absorbers on your vehicle need replacing, particularly the front ones which affect steering, if you need to drive on a high-speed freeway.

Handling, steering, traction and ability to brake quickly are all impaired when the shock absorbers are worn, particularly the front ones which carry the majority of the weight of the engine bay and which are connected to the front, steering wheels.  Add to this the peril of reverse-cambered sections of freeways and there is significant risk involved, which should not be ignored.

I donít drive at more than 90km/h when the shock absorbers on my vehicle are worn and need replacement because the vehicle is unsafe at such higher speeds, particularly on curved sections and particularly when itís the front shock absorbers that need to be replaced.  Furthermore, I avoid freeways altogether until theyíve been replaced since driving at only 90km/h is not fast enough to avoid mishaps with other faster-travelling vehicles on freeways.

An easy way to determine whether a shock absorber at one of the four wheels of your vehicle is worn is to bounce the body of the vehicle hard up and down with your hands at that particular wheel and then watch to see how the body of the vehicle moves up and down until it comes to rest again.  If the body of the vehicle quickly comes to rest after just a couple of oscillations up and down, because the shock absorber is deadening the bounce of the vehicle, then you can be sure that the shock absorber at that particular wheel is still functioning correctly like it should.  However, if the body of the vehicle bounces up and down freely and doesnít come to rest after just a couple of oscillations up and down, but keeps on bouncing because the shock absorber at that particular wheel isnít deadening the bounce of the vehicle, then you can be sure that the shock absorber at that particular wheel is no longer functioning correctly and should be replaced as soon as possible.

Shock absorbers should always be replaced in left and right front or left and right rear pairs, otherwise the handling of the vehicle on the road can be impaired from mismatched left and right shock absorbers which exhibit different performance characteristics due to different levels of wear.  Itís also critically important that the make and model of the left and right shock absorbers on the front or rear of the vehicle is the same, so that the left and right shock absorbers exhibit the same performance characteristics.  For example, if you test the shock absorber at the front left wheel and find that itís no longer functioning correctly, then both of the front left and right shock absorbers should be replaced as a pair with the same make and model of shock absorber thatís suited to your particular vehicle.

Replace worn-out suspension bushesÖ

Replace worn-out suspension bushes with high-quality bushes, such as those made out of polyurethane, in order to maintain the performance of the suspension system and the handling of your vehicle.  Worn-out suspension bushes can introduce play and movement into the suspension system of your vehicle that shouldnít be there, which degrades the handling of your vehicle and can even render it dangerous if the worn-out suspension bushes arenít replaced.

Understanding the function of the different suspension bushes throughout your vehicle requires somewhat specialist knowledge.  For this reason, itís important that you take your vehicle to a qualified suspension expert every twelve months to check over the suspension system.  He or she will be able to expertly determine whether any suspension bushes need to be replaced and can easily detect problems that you might not otherwise be aware of.

Get a front wheel alignment every six months...

Itís important to get a front wheel alignment (and a rear wheel alignment also if the alignment of the rear wheels on your vehicle is adjustable) every six months to ensure that the steering of your vehicle remains accurate and safe.  Over the course of six months, itís inevitable that the wheel alignment will go out of adjustment due to the many bumps encountered on the road.  You can feel when the front wheels are out of alignment while driving and holding the steering wheel because the vehicle moves less nimbly and more ponderously.  In addition, when steering around corners, the vehicle can feel as though itís fighting you and you have to concentrate harder and apply more effort to steer the vehicle exactly where you want it to go.

Probably the easiest way to determine if the wheels are out of alignment is by taking your hands off the steering wheel momentarily when the vehicle is travelling in a straight line on a level road.  (You should obviously keep your hands hovering over the steering wheel, ready to take back control after a second or two, to avoid having an accident.)  If the vehicle continues travelling in a straight line then the wheel alignment is good.  However, if it veers off to the left or to the right, then the wheels are out of alignment.

Be careful about driving too quickly over bumps in the road (eg. potholes) or traffic calming devices installed on the road (eg. speed bumps) which might cause the front wheels of your vehicle to become misaligned, thereby impeding accurate steering of the vehicle and possibly the safety of the vehicle also.

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