When to Replace Your Tyres

Tires are more important than we care to think about, as the part on which your car drives. Having the right package for the path is only just a good start. A few hundred miles later, even the best of tyres slowly begin to wear off, impacting the car's performance and health. Often tyres are both the most ignored part of any trip and the most critical one. As the final gear between your car and the ground, all the force of your acceleration, braking power, and turning torque must be transmitted through your tyres, before you even move an inch of your vehicle. Even if you have the world's most powerful car, it doesn't mean anything if you don't have the right tyres.

Reasons for changing tyres
Of course there are several factors that may lead to ageing. Yet what makes tyre wear bigger? 
1. Driving style: rotating the wheels or locking them when braking increases wear
2. Bad roads
3. Alignment: Incorrect alignment can lead to rapid and inconsistent wear off of tyres
4. Speed: Driving at high speed raises temperature and wear (check the speed index)
5. Position: Front wheel drive cars usually show greater wear on front tyres
6. Load: Excess load on cars increases wear (check the index of load)
7. Pressure: One of the most important things you can do to look after your tyres is maintaining the right inflation rate. Wear will rise both under inflation and over inflation.

The fundamentals of replacing tyres The key rule for replacing the tyres is depth of tread.
Besides tread width, when testing for roadworthiness, you want to consider the age of your tyres. Here are some simple guidelines to test your tyres. 

• By regulation the tyre's tread depth must be at least 1.6 mm deep to be deemed roadworthy in Singapore. 

How long will tyres last in years, and what is the lifetime of the car tyre? Most tyres feature tread wear markers (small bars around the tyre's grooves, at precisely 1.6 mm) to make this easier. When your rubber is flush with the rubber wear indicator it's time to change your tyres.

• If your tyres are older than 5 years, they should be inspected once a year. 
  
• If your tyres are over 10 years old they should be immediately replaced.
  

Even if they still have tread, rubber deteriorates with age and breaks, so it's best to only remove them. 

Tip: Tires are better substituted in full sets. This way, you're not having uneven wear between tyres, so your car runs better. 

When you need to replace less than a complete set, it is better to do so in two sets and put the new ones on the rear for maximum traction (unless you drive a front wheel drive, in which case you can put them in front of you).

Let's look at a few hints and tips to help you recognise a damaged tyre:
How to improve your tyres' lifetime and efficiency.
1. Test the depth of tread The depth of the tread is a consideration to remember when changing tyres. Both tyres have tread wear indicators which are small rubber blocks moulded at regular intervals in the tread grooves. Those blocks get closer and flush with the tread surface as the tyre wears. Which is the legal limit on depth of tyre tread in Australia? The minimum permissible depth of tread over the width of the sole is 1.5 mm. If you're not sure if you're going to have an illicit tread follow these easy steps and you're going to be free.

2. Search for uneven wear Uneven wear is a sign that shows more stress on the tyre than usual. This may be due either to improper wheel alignment, worn suspension, or you were driving under or over-inflated with the tyres. Inspect the entire contact surface including the outer edges of the tyre to test for irregular wear. Our interactive animation will teach you in detail about the tyre wear. 

3. Check the tyre Age Experts say that a tyre that is over five years old will need replacement because the rubber loses its suppleness by drying out moisture and oils.The age of a tyre may be determined by examining the date of manufacture printed on the sidewall, usually as a four-digit number, where the first two digits reflect the week of manufacture and the last two digits reflect the year. 
A decent set of wheels has a big part to play in bringing you a comfortable ride, healthy handling of fire and enhanced economy of fuel. The condition of the rubber on which your vehicle sits can also mean relaxed braking and comfortable driving. Check your tyres regularly and you know it's time to change them if there are signs of wear and tear.

4. Check your air pressure Testing your air pressure frequently goes a long way to improving the lifetime of your tyre (Here is a helpful guide on how to correctly test the air pressure). Getting over or under-inflated tyres, leads to uneven strain on the treads, which can begin to show up as an irregular wear pattern Driving with over-inflated tyres, wearing down the middle of the tread when driving with under-inflated tyres, creates wear close to the tread shoulders.
Driving with underinflated tyres not only will cause unnecessary uneven wear, but will also reduce your fuel economy. It's calculated that your tyres are under-inflated for every 3 psi (pounds per square inch), you lose 1 percent fuel economy, and you add 10 percent more tyre wear. It is best to test your air pressure for filling your tank at least once a month (if not every time you stop). Bear in mind also that temperature differences influence your air pressure-cooler temperatures will cause your air pressure to drop, whereas hot temperatures will cause it to increase. A general rule of thumb is to keep the tyres between 30-25 psi (pounds per square inch) anywhere.

5. Check your tyre alignment Test your alignment (ideally every 5000 km) to really get the most out of your tyres. It is a long way to having even more wear on your tyres, and optimizing your results. Wheel alignment has three components: Camber (vertical inward or outward tilt) Toe (like pigeon-toed or duck-footed in humans) Caster (displacement from the steering axis) Tyre alignment problems manifest as wobbling, pulling to one side, or failing to adjust the wheels after straightening out of turn. Getting unaligned tyres results in unpleasant, irregular wear patterns such as cupping, feathering, unilateral wear and others. Such uneven wear reduces the performance of your tyres, your vehicle and wears down your tyres more quickly. It can be expensive to have the tyres matched but the expense is well worth it. You can read the full guide to wheel alignment here. 

6. Routing your tyres periodically As your tyres, depending on their location, wear differently, it is best to rotate them sometimes to wear even out. When your car is a rear-wheel drive, for example, the rear tyres can wear more easily (and vice versa for front-engine vehicles). It is best to rotate tyres periodically to reduce the wear distance between front and rear sets of tyres.The more often you spin, the more wear you get (and more out of your tyres). Rotation pattern depends on whether the vehicle is forward wheel drive, rear wheel drive, and directional or non-directional tyres. Check out how to rotate the tyre. 

The key causes of damage to tyre Basically there are two ways of damaging the tyres: those you manage and those you don't. Luckily the most common causes of damage to the tyre are largely within your influence. 

• Driving at high speed and abrupt braking, which causes heat build-up, loss of air and abrasion. 
• Over- or underinflation which leads to irregular wear of the tread.
• Overloading, giving your car too much weight and putting a lot of tension on your tyres. Road hazards are the remaining common causes of tyre-damage. While you can't control the roads, by just driving more slowly and cautiously, you can avoid hazards like potholes, debris and curbs. 

How many kms are tyres to last? 
Mileage from tires, from driver to rider is highly variable. Your personal mileage depends on your car, driving style and conditions on the local roads. It is fair to expect about 40,000 km of life out of the tyres, for the average collection of tyres. Taking into account the average Aussie drives about 15,000 km a year, the average driver should expect their tyres to last 2-3 years. Your mileage will vary, once again. Drivers that treat their tyres kindly may be able to stretch them up to 80,000 km, while the tougher driver can get just 10,000 km. Evidently, the faster you drive (with less sudden accelerations or braking), the longer the tyres. Driving on smoother roads and in more temperate climates often prolongs the lifetime of the tyre. There are the top three things you can do to improve the lifetime and efficiency of your tyres, to really get the most out of your tyres.
Depending on the type of vehicle, its use and, finally, the age of the tyre itself, there comes a time when replacement is needed. All car owners should be conscious of the right time to remove the damaged tyre. When you're not an expert you'd be able to tell your mechanic if your tyres need a change. In general, the indicators are basic and mean nothing more than a visual search. 

Conclusion
Having a new set of tyres instantly improves your car's performance, mileage and sound. 
It's very easy to test when to remove your tyres (depth of tread 1.6 mm).
Properly driven, anyone can extend the lifetime of their tyre well beyond average mileage. Checking your alignment periodically, air pressure and rotating your tyres, would also greatly improve their lifespan (as well as the output of your car).