All you need to know about tyre maintenance

It's important to periodically check and carry out maintenance on your tyres. Find out here about vehicle alignment, tyre rotation, tyre balancing, tread wear and other key aspects of maintaining your tyres.

Wheel alignment

It is important that every vehicle has its 4 wheels correctly aligned. Unaligned wheels will fight the natural motion of the vehicle causing steering problems, driver fatigue, and premature and irregular tyre wear.     

In its most basic form, a wheel alignment consists of adjusting the angles of the vehicle's wheels, this to make sure that the wheels travel in relation to the geometric centreline of the vehicle. Each wheel has its own set of dynamics (camber, caster and toe) specified by the automobile manufacture.    

The most common symptoms of a car that is out of alignment are uneven or rapid tyre wear and when the car is pulling or drifting away from a straight line. When you notice these kinds of problems on your car your wheels are most probably not properly aligned. In such a case FULDA recommends to have your vehicle alignment checked by a specialist, who is using modern computer aided vehicle alignment equipment. Today many tyre specialists and car dealers have such sophisticated equipment and offer vehicle alignment services.     

The best type of wheel alignment is a four wheel alignment. For this type of alignment the technician will place an instrument on all four wheels and measure the vehicle dynamics on all four wheels. Today, many cars have adjustable rear alignment settings, but even for cars without adjustments in the rear, a four wheel alignment will allow the technician to identify any rear tracking problems and compensate them with adjustments to the front. The two wheel alignment, in which only the front wheels are aligned to the centreline, has become obsolete.      

Tyre balancing

Out-of-balance tyres cause a car to vibrate at certain speeds. This can lead to premature, irregular tyre wear, as well as unnecessary wear to your vehicle's suspension. Make sure your tyres are balanced when they are mounted on wheels for the first time or when they are remounted after repair. Tyre balance should be checked at the first sign of a vibration.

The best way to explain tyre balancing is to begin to explain what a lack of balance is. When a tyre is mounted onto the wheel, two slightly imperfect units are joined to form an assembly. The chances of this assembly having absolutely precise weight distribution about its radial and lateral centres are virtually impossible.
Usually wheel can present two types of imbalance: Static imbalance and dynamic imbalance.

Static Imbalance: Occurs when there is a heavy or light spot in the tyre. In this case the tyre does not roll evenly and the tyre and wheel undergo an up-and-down motion.

Dynamic Imbalance: Occurs when there is unequal weight on one or both sides of the tyre/wheel assembly's lateral centreline. Dynamic Imbalance can cause a side-to-side wobble or wheel shimmy.

Most assemblies have both types of imbalance, and require dynamic balancing to create even weight distribution. To balance the wheel, the technician mounts it on a balancing machine, which spins the wheel to locate the heavier parts of the assembly. The balancing system then directs a technician to place counter weights on the rim's surface to offset the imbalance.

Tyre Inflation

Note that it is important to check your tyres inflation including the spare tyre at least once a month with an accurate tyre pressure gauge. With the right amount of air pressure, your tyres wear longer, save fuel, enhance handling and prevent accidents. If you consider the liabilities of not maintaining the correct air pressure -- poor fuel mileage, loss of tyre life, bad handling (perhaps even loss of control), and potential vehicle overloading -- then the need to routinely checking of your tyre inflation will become clearer.

Checking tyre tread

Fulda recommends to check your tyre tread regularly to find out whether a tyre needs replacing. All passenger, light truck, and medium commercial tyres have tread wear indicator bars moulded in the tread. These bars are located at the bottoms of the tread grooves in several locations around the tyre. Their location is indicated in the shoulder area by little triangles. If the tyre is worn to the point that the treadwear indicators are at the same height as the adjacent tread ribs, this means that the tyre has only 1.6mm of tread depth left. You should replace your tyres immediately, as 1.6 mm is the legal minimum tread depth required by law.

The performance of a tyre on wet roads decreases with the remaining tread depth. With a reduced tread depth the tyre is not able to evacuate the same quantity of water  as before and therefore the risk of aquaplaning increases. Moreover, the braking performance on wet roads is reduced. It is therefore generally recommended, to replace your summer tyres when less then 3 mm profile depth is left.

Fulda winter tyres are equipped with special winter wear indicators. The locations of these winter wear indicators in the tread are indicated in the shoulder area with a snowflake. When the tyre is worn to the point that the winter wear indicators are at the same height as the adjacent tread ribs the tyre has only 4mm of tread left. It is generally recommended to replace winter tyres with less than 4mm profile depth, to ensure optimum safety in winter conditions.

If your tyres wear off irregularly, this may be an indication your tyres don't have the optimum tyre pressure or that your car has some kind of chassis problem.

If the tread is deeper on the edges than in the centre, the tyre is possibly over inflated.

If the tread is deeper in the centre than the edges, the tyre is possibly under inflated.

If the tread is deeper on one side than the other, have your wheel alignment checked soon.

Where To Find Air Pressure Information?

The correct air pressure may be found in the vehicle owner's manual or on the tyre sticker (attached to the vehicle door edge, doorpost, glove box door or fuel door). If you cannot find the air pressure information Fulda advises you to, contact a local tyre dealer for assistance.

How To Check Air Pressure?

Many people believe that they can check air pressure just by looking at the tyre and judging the sidewall appearance. However properly checking tyre pressure requires an accurate air gauge. Note that air meters at service stations, can be grossly inaccurate due to exposure or abuse. The best way to check your tyre pressure is to visit your nearest tyre dealer.
When checking your vehicle's tyre pressure, make sure the tyres are "cold". Cold air pressure means that the vehicle has not yet been driven (remember that driving on a tyre increases its temperature and air pressure).

Tyre rotation

Rotating your tyres periodically is an important part of tyre maintenance. The main purpose of regularly rotating tyres is to achieve more uniform wear for all tyres on the vehicle. If no rotation period or pattern is to be found in your owner's documentation, rotate your tyres at least every 8.000-km to 10.000 km. However, rotate your tyres earlier if irregular or uneven wear develops, and check with a qualified tyre dealer or alignment shop to determine the cause of the wear problem. Remember that a hard impact such as hitting a pothole can cause misalignment, which then causes uneven tyre wear.

On front wheel-drive cars, it is especially important to rotate your tyres periodically because the front tyres wear faster than the rear tyres. Uneven tyre profile depth, front to rear, will give you uneven braking and poor handling, especially in the rain. If you don't rotate the tyres, you'll wind up replacing them two at the time, which means you'll always have uneven tread thickness. Replacing tyres in a matched set of four will keep the handling and braking traction of the car balanced.

Note: Pay attention if you have directional tyres. They should not be crossed overt to the other side of the car, but only switched from front-to-rear, to avoid the tyre to rotate in the wrong direction. To be sure if your tyres are directional please check the tyre sidewall for an arrow with the word "rotation" on the sidewall.