Second-hand (part worn) tyres

The safety of a tyre is directly related to how long it has been used for. So if you’re thinking of buying second hand tyres, remember what they could cost you.

In its latest campaign the RSA has highlighted the cost and potential danger of buying second hand (part-worn) tyres. Second-hand or part-worn tyres are tyres which have been used on another vehicle. Such tyres can pose a serious road safety risk. The history of a second hand tyre is relatively unknown - it could have been involved in a crash or have internal damage, which may not be visible once fitted to your vehicle. Even if these tyres meet the minimum thread depth requirements, they may not uphold in an emergency braking or steering situation.

Second hand tyres – are they as cheap as you think?

Make sure you know what your legal requirements are before considering a second hand tyre. It is an offence to drive with defective or worn tyres and you risk a fine of €80 and up to 4 penalty points upon conviction.

You should also think about whether or not you’re getting real value for money. For example; a second hand tyre costing €30 has tread thickness of 3.6mm. Therefore, it has 2 mm of useable tread before it reaches the minimum legal tread depth of 1.6mm. This works outs at €15 per mm of usable tread.

On the other hand, a new tyre costing €80 has 8mm of tread. Therefore, it has 6.4 mm of useable tread before it reaches the minimum legal tread depth of 1.6mm. This works out at €12.50 per mm of useable tread, and therefore offers better value. In addition to the increased costs in this example, you would have to buy and fit three sets of these part worn tyres in order to get the same life as one new set of tyres.

The following are some important safety points to look out for if you’re considering buying a second hand tyre:

1. Check for an E-Mark on the tyre (Figure 1). Your tyres will need to carry an E-mark for the NCT.

Figure 1: E-Mark and S-Mark on tyre sidewall

2. Check that there is a minimum tread depth of 1.6mm on the tyre. Anything less is illegal for use on a public road. A tyre’s tread depth can be measured by using a tread depth gauge or using the pop out card in the leaflet entitled “Your Guide to Tyre Safety”. 

Always measure in the middle of the tyre surface, and not at the edges. (Figure 4).

 tread depth

Figure 2: Tyre tread depth

3. Tyres also have a ‘tread wear indicator’ block set into them at a depth of 1.6mm. You should check this block to ensure that this indicator is not at the same level as or lower than the tyre tread.

 tread wear indicator
Figure 3: Tread wear Indicator block

pop out tyre gauge

Figure 4: How to use the handy pop-out tyre tread depth gauge available in the printed version of the leaflet entitled “Your Guide to Tyre Safety (PDF)”.

4. Ask the seller if the tyre has undergone a condition check (including when it is inflated) to make sure it meets the minimum legal requirements and is free from defects both internally and externally. Common defects include tears, lumps and bulges. A tyre that is not roadworthy will result in a car failing its NCT as well as reducing your safety on the road. Examples of particular tyre defects are shown below.

tyre damage 

5. Ask the seller to confirm that the tyre you are buying is the correct size and design for your vehicle, and that it has the correct load and speed rating for its intended use. If you’re not sure about what tyre is best suited for your vehicle, you could consult your vehicle manufacturer or look it up in the owner’s handbook.

6. Find out the age of the second hand tyre and make sure that it is not more than six years old. A tyre that is six years old is a ‘pass advisory’ item at the NCT. A tyre’s age can be determined by the serial number on the tyre sidewall. This serial number comprises of a four digit code as shown in Figure 6 and refers to the tyre’s date of manufacture. The last two digits refer to the year or manufacture; the first two refer to the week in that year. For example, 1411 = week 14 of 2011.
production date code
Figure 6: Production Date Code 2014 = 20th week of 2014

Tyres deteriorate with age. Signs of tyre aging include cracking or crazing (lots of fine cracks) on the side wall of the tyre caused by the tyre’s flexing movements. The shape of the tyre tread can become distorted too. Tyre aging increases the risk of tyre failure. Tyres may begin to show the signs of aging from when they are six years old.

7. Be aware that there could be damage to the inside of the rubber which you mightn’t be able see from just looking at it, but that it would be possible to see in an x-ray. The seller might be able to show that the tyre was x-rayed to prove that there is no internal damage.

8. Be satisfied that you are getting value for money. The remaining tread depth of a secondhand tyre is very important, and this is something you need to consider carefully in terms of the value for money. To check the percentage of usable tread remaining, use the popout tyre tread depth gauge provided in the “Your Guide to Tyre Safety” Booklet. .