Because it’s the only part of the vehicle that grips the road, the depth of tread on your tyres is a very important for the safety of your vehicle. It also signals the health of the tyre. Driving with low tread depth increases the potential for tyre failure and aquaplaning. Low tread depth in winter weather conditions can severely reduce grip and control. Motorists driving with tyres under the legal limit also risk a fine.
The legal minimum limit for tyre tread depth in Ireland is 1.6mm. This is because, tyre performance, particularly in wet weather gets worse as the tread wears down.
The greater the wear to your tyres the worse its wet weather grip will be.
How to check your tyre's thread depth
Step 1 - Access the tyre tread
The first step in checking tyre tread depth is to get good access to your tyres.
- Park on a wide, flat and even surface in a safe place off the public highway with the engine switched off and put the keys in your pocket.
- Put on the handbrake (parking brake) and engage first gear (for manual gearboxes) or park (for automatics).,/li>
- Once you have clear and safe access to the tyres you can begin the inspection.
Step 2 - Check the tread
With the tyre tread you can begin to check the depth of the tread and the condition of tyre. Don’t rely on guesswork: purchase an easy-to-use tread depth gauge so that you can monitor your tyres. Measuring tread depth is not difficult with this simple device and requires only a few minutes of time.
The legal minimum tread depth in Europe is 1.6 mm across the central three-quarters of the tread width and round its entire circumference. Check the depth of the main tread grooves in several places across and around the tyre, using the gauge as instructed by its manufacturer. Tyres also have tread wear indicators moulded into the base of the main grooves. When the tread surface is worn to the same level as these indicators, the tyre is at the legal limit and should be replaced.
However you check your tyre tread depths, if they are approaching the legal limit or if you have any doubts, when not get them checked professionally by one of our tyre specialists.
Having the correct inflation pressure in your vehicle’s tyres not only optimises their performance but also increases your personal safety, and the safety of others, when driving.
Driving with incorrect tyre pressures can affect a vehicle’s handling, and can seriously compromise safety - possibly leading to incidents that can put lives at risk.
As a guide you should check your tyre pressures at least once a month, and before long journeys (failure to do this will mean you run the risk of decreasing your grip and increasing your braking distances; plus you could also damage your tyres, reduce their lifespan and increase your fuel consumption!).
The recommended tyre pressure levels for front and rear tyres are often different. The correct pressures for your vehicle can normally be found in your owner's manual. The information may also be marked on the vehicle (for example on the driver’s door pillar, or on the inside of the petrol flap).
In most cases, two different sets of pressures are given:
- For 'normal' driving conditions.
- For a loaded vehicle (with extra people or heavy items on board).
To check your tyre inflation pressures you will need a tyre pressure gauge or use the gauge on the inflation equipment found at most garages and petrol stations.
Check your tyre pressures at least once a month!
If you want to know more about your tyres, you need to be able to decode what is written on its side. Your car manual will have information you will need as to what type of tyres are compatible with your vehicle.
What are the codes on the side of my tyres?
The first code indicates the size of the tyre and the second indicates the load and speed that it can operate up to.
205/55 / R16 91V
(width/height/diameter/load index/speed index)
1) Tyre Width (205)
The number 205 indicates the width in millimeters. For standard tyres, this number varies between 125 and 335 millimeters.
2) Section Height (55)
55 is the height of the tyre section, expressed as a percentage of the width. In this example, the height is 55% of the total width of 205 mm, which is 112,75 mm.
3) R
The letter R stands for Radial, the type of tyre. You may also see ZR indicating the tyre is for high speeds or RF which indicates that it is a Run-Flat tyre. Although the majority of tyres are now Radial type, a bias, or cross-ply, construction tyre will have a “-“ in this position.
3) Diameter (16)
16 is the diameter of the tyre’s inner rim. It is always expressed in inches. The number varies between 10 and 23 inches for passenger vehicles.
4) Load Index (91)
91 is an index of the maximum load carrying capacity per tyre at the speed designated by the speed symbol (91 = 615 kg).
| Load Index | Kg | Load Index | Kg | Load Index | Kg |
| 65 | 290 | 80 | 450 | 95 | 690 |
| 66 | 300 | 81 | 462 | 96 | 710 |
| 67 | 307 | 82 | 475 | 97 | 730 |
| 68 | 215 | 83 | 487 | 98 | 750 |
| 69 | 325 | 84 | 500 | 99 | 775 |
| 70 | 335 | 85 | 515 | 100 | 800 |
| 71 | 345 | 86 | 530 | 101 | 825 |
| 72 | 355 | 87 | 545 | 102 | 850 |
| 73 | 365 | 88 | 560 | 103 | 875 |
| 74 | 375 | 89 | 580 | 104 | 900 |
| 75 | 387 | 90 | 600 | 105 | 925 |
| 76 | 400 | 91 | 615 | 106 | 950 |
| 77 | 412 | 92 | 630 | 107 | 975 |
| 78 | 425 | 93 | 650 | 108 | 1000 |
| 79 | 437 | 94 | 670 |
5) Speed Index (V)
The last letter indicates the maximum speed for the tyre at full load. V corresponds to a maximum speed of 240 km/h. This should generally be higher than your vehicle’s maximum speed. However, there are exceptions for winter tyres and exemptions in some countries. Be careful not to have tyres with a lower speed rating or load capacity (see above). Your vehicle’s manual will provide more detail.
| Speed Index | ||||||||||||||
| GI | M | N | P | Q | R | S | T | U | H | VR | V | ZR | W | Y |
| km/h | 130 | 140 | 150 | 160 | 170 | 180 | 190 | 200 | 210 | >210 | 240 | >240 | 270 | 300 |
6) Model Name
The model name of the tyre - unique to each manufacturer.
7) Maximum Load
The maximum load the tyre is designed to carry (in both kg and lbs).
8) Maximum Pressure
The maximum pressure the tyre is designed to be inflated to (in both bar and psi).
9) Brand Name
The manufacturer/brand name of tyre.
Tyres can be classified according to three distinct categories as follows: 1) summer tyres 2) all-season tyres 3) snow or winter tyres
Most tyres used in Ireland are categorised as summer tyres. This does not mean that they are for use during the summer only—it’s merely as a way to segregate them from winter tyres in countries where there is a practical and sometimes legal requirement to fit winter tyres.
Snow/Winter Tyres
Snow tyres have tread patterns specifically designed to bite into snow and ice. They’re made from softer rubber compounds that retain their flexibility in cold weather, allowing the tyre to better conform to the surface of the road; whereas summer and all-season tyres get hard and are less pliable in cold temperatures.
As a result, winter tyres give better grip on snowy and icy surfaces than regular all-season or summer tyres. Grip is critical—not just to avoid getting stuck, but to ensure that a vehicle can stop and steer and ensure safety enhancing technologies such as Antilock Braking Systems (ABS), Electronic Stability Control (ESC) and all-wheel drive can do their jobs.
All-season tyres are designed to cope with all sorts of conditions, including dry roads and rain, but are not optimised for any one condition.
Tyres that meet new American and Canadian winter tyre standards are marked with the symbol of a snowflake on a mountain on their sidewalls as shown below.
Winter tyres - should I fit them?
Currently there are no specific requirements in Irish Road Traffic Regulations mandating or prohibiting the use of snow or winter tyres.
Our advice is that, should you wish to install a set of snow tyres, you always install a full set of four to reduce the risks of over and under steer.
Once the possibility of snow is gone, you should remove your snow or winter tyres and reinstall your all-season or summer tyres (as they are made from softer compounds, which cause them to wear out faster, especially in warm weather).