Tyres are one of the items that you will regularly have to replace on your car so it’s worthwhile knowing a bit of info on them. Even if your car is mechanically sound, tyres are a wear and tear item so eventually will need replacing regularly. Let’s take a look at some of the most frequently asked questions we get.
Can tyres be different brands?
We wouldn’t recommend mixing different tyre brands, but it is something we see often. Each tyre is designed with the assumption that the other tyres on the vehicle will be matching so they will all be working together in unison. When you have a mixed set of tyres you can expect:
- Affected steering, handling and acceleration
- Braking distances to increase
- Possible inaccurate speedometer readings
- Extreme instability in bad weather
- In long-term use, uneven tyre wear could affect the clutch
Should I rotate my tyres?
Many people ask us why you should rotate your tyres and there are a few key reasons. Regularly rotating your tyres can increase their life span. This gives you a chance to get all your tyres worn at the same speed and can give you peace of mind that your spare tyre is in good condition. It can be done, but it’s not necessary.
Can tyres cause vibration?
Poor tyres can be a reason for feeling vibration and it could be caused by a number of reasons.
- A buckled or cracked wheel
- Uneven wear of the tyres including deformities like bulges
- The wheels are not being balanced correctly
- Off-centred wheel alignment
- Damaged suspension
What are run-flat tyres?
Run flat tyres are built with reinforced sidewalls so if you get a puncture, you can continue driving but only for a limited distance at a limited speed. Most run-flat tyre manufacturers recommend not driving over 50mph and for a maximum distance of 50 miles. The thing to remember with run-flats is that they give you an opportunity to drive to a garage to get a new tyre, but they don’t allow you to continue driving long-term. If you continue driving on a run flat that is punctured you run the risk of damaging your wheel, which is much more expensive to replace (around £1000 for a Mercedes wheel rim). Run flats must be used in conjunction with your tyre pressure monitoring system (TPMS) so you are notified of when you get a puncture.
This graphic from Continental shows how the reinforced sidewalls protect you even with a puncture.
The three main advantages to run flat tyres are:
- The strengthened sidewall will help to keep you stable in the event of a puncture
- You won’t need a spare wheel in the boot which will save space and improve fuel efficiency
- You don’t need to change your wheel at the side of the road which is a pretty dangerous situation to be in
Do tyres affect fuel consumption?
Tyres do affect your fuel consumption, but this will be clearly labelled on the tyre information when you purchase it. Jump to the bottom of this page to see more about tyre labels and their meaning.
It’s estimated that tyres are responsible for around 20% of your vehicle’s fuel efficiency, mainly because of their rolling resistance (aka rolling friction or rolling drag). This is the resistance generated between the road surface and the tyre and can be affected by the tyre material.
Lowering your rolling resistance can help to improve your fuel efficiency. For example, if you choose a tyre-rated class A over a class E, you could save up to 80 litres of fuel per year which will add up to more than £100 of savings! And of course, better fuel consumption helps the planet as you are producing fewer CO2 emissions.
Should I look at winter and summer tyres?
A general rule of thumb is that once the average daily temperature is below 7°C, switch to winter tyres and when the temperature averages above 7°C, it’s time for your summer tyres. You definitely should not use winter tyres in the summer or vice versa.
Winter tyres have been created with a slightly different mix consisting of more natural rubber and silica and the tread is usually deep cut, in chevron patterns. This makes sure that winter tyres are more flexible in cold temperatures whereas a normal set would become firm and provide more grip and traction.
Summer tyres however are made from a hard compound mix that softens in mild temperatures. They are able to provide a high grip level on wet and dry roads thanks to their specific tread patterns which are usually orbital going around the tyre.
Where can tyres be repaired?
If you have a puncture that is troubling you, we can fix it for you! We can also order tyres for you and do the tyre fitting too. If you need your tyres rotating whilst you’re here that’s not a problem either.
Can tyres fail MOT?
Yes, you can fail your MOT on your tyres, and it’s actually a really common fail item. The MOT tester will first check that your tyres are suitable for your vehicle. The tread depth needs to be at least 1.6mm, and there must not be any cuts that are larger than 25mm. They will check the tyre for lumps, bulges, tears, tread separation and any exposure of the cord.
Why does tyre pressure change?
It’s normal for your tyre pressure to change, Michelin estimate that you should expect to see your tyre pressure drop by 1psi per month. However, if you are losing pressure a lot more often than this, you may have an issue with your tyre. This could be due to:
- A slow puncture
- The valve, which should be changed every time the tyre is changed
- The valve cap, which when working properly ensures an airtight seal
- The wheel may be damaged, a buckle or crack can present signs of a slow puncture
- The temperature dropping in winter
It doesn’t take much difference in tyre pressure for you to see a difference in efficiency. Just 7psi below the tyre manufacturer’s recommendation could see your tyre’s lifespan reduced by almost 5000 miles.
A properly inflated tyre improves road safety, tyre efficiency and is better for the environment.
How to read tyre labels?
This is what you can expect to see on a tyre label
so let’s look into each of the icons and their meanings.
Fuel efficiency/rolling resistance
Fuel efficiency is important as it can reduce your fuel costs and your CO2 emissions too.
Tyres are rated between A – E. A is the most fuel-efficient, and E is the least. The difference between each rating equals a reduction or increase in fuel efficiency of 3-4%.
Wet grip/braking performance
The wet grip of your tyres is a critical safety element showing how quickly your car can stop on wet roads.
Tyres are rated A – E. A is the shortest braking distance in the wet, and E is the longest. The difference between each rating is equal to an extra 3-6 metres (one or two car lengths) on the stopping distance.
Noise emission/exterior noise
The noise emission states how much external noise is generated by the tyre and is measured in decibels (dB).
Tyres have three ratings for noise – A, B and C. Rating A creates the least external noise, and rating C creates the most.
Three Peaks Mountain
The 3 peaks mountain which was previously seen on the sidewall of tyres will be replaced with a snow and ice grip picture on the label.