How to Measure Tyre Tread Depth.

How to test your tyre tread depth with different tools. Please like and subscribe for more content.

Transcript

00:00Hi everyone just a quick video on tyre tread depths and the legalities of them so we've got

00:06three ways of testing it we've got the digital tread depth gauge here which is about £10 we've

00:11got the old mechanical traditional one here that's about £3 and we've got a quick test you can do

00:15with 20 pence a piece if you just want to check if your tyre is legal or not so what is legal or

00:21not so for looking at the tyre here in the UK you're tested on the middle 75% of the tyre so

00:28the two shoulders are not tested they can be bald as long as they've not gone through so you can see

00:33the cord or the construction of the tyre that bit's fine so it's the middle 75% and in this

00:39country it's 1.6 millimetres so the tread depth in this tyre must be 1.6 millimetres or greater

00:44you normally get advisers at MOTs from about 3 millimetres downwards because between 3 millimetres

00:50and 1.6 millimetres the water clearance efficiency reduces massively and the stopping distances are

00:56up to double bear in mind the brand new tyres between 6 and 8 millimetres depending on the

01:01manufacturer so the three ways of testing it then so I've got the digital one here this one's nice

01:07and easy you can just turn it on you'll see there and we've got it'll tell you what it is a millimetre

01:12I'll just push that back to flat I will zero it and then I'll put it against the tyre up here

01:18and I'll push down in the groove there and it will tell me this tyre has 5.78 millimetres of tread

01:28now the other important thing about doing tread depth is that you should test it evenly or roughly

01:33evenly in three places because a tyre can go something called out of round which basically

01:38means it has high spots and low spots and if it has high spots and low spots you might not capture the

01:44low spot and therefore you might miss it so 5.6 there and then another third of the way around

01:49obviously if you don't have the luxury of a ramp then you can always just roll the car backwards

01:53and forwards and then one more time we have 5.65 so this is quite consistent all the way around

01:59the other one obviously is this old mechanical one here I won't show you on the tyre because you've

02:04just understood what to do and as you can see it's gauging millimetres and they're stepped

02:08so as you push down in the groove obviously wherever the casing ends and the line under the number

02:14is then that's what it represents so there you've got just about eight millimetres if that was against

02:21the car you scroll it right up they're normally whole numbers apart from this bit where it says

02:251.6 millimetres because again that's the legal minimum in most most countries so again if that was

02:32down and below there then you'd be fine if that was up and raised above there then you've got an

02:37legal tyre and the two quick ways of checking just if you want to know if your tyre is legal or not

02:41it's the old 20 pence piece trick so the border on this 20 pence piece there is exactly 1.6 millimetres

02:47so if I place it in the tread tread area like that if I can't see the edge of the border then it's a

02:54legal tyre if I could see the border sticking out like so then that would tell me that tyre's under 1.6

03:01millimetres and I need to change it and it will fail an MOT but as it is that's absolutely fine

03:06last thing as well on tyres that people don't realise is you've got these tread wear indicators

03:11so those the tops of those are 1.6 millimetres from the bottom so when you've got an MOT and you're

03:18just looking at a tyre casually or if you're looking at your own tyre if that is scrubbing on the road

03:23as this tread's worn down then that actually means that it's under 1.6 and it's a legal tyre

03:29once that starts touching the road surface and scrubbing against the tarmac so

03:32I hope that all makes sense and we'll see you in the next one