Tyre tread depth

pseudodox

cymruchris said:

Keep in mind age as well as depth. As tyres age, they crack. So if you're doing tiny mileages, and wearing your tyres out slowly - keep an eye on the sidewalls as well - and replace them after about 7 or 8 years even if they still have good tread.

My car has failed MOT more than once for this very reason.  This year it passed but advisory notice referred to this issue with 2 tyres as I do very low mileage.  I got them replaced ahead of a longish journey.  Better safe than sorry as I did once have a tyre with good tread blow on the motorway - terrifying!

HillStreetBlues

pseudodox said:

My car has failed MOT more than once for this very reason.  This year it passed but advisory notice referred to this issue with 2 tyres as I do very low mileage.  I got them replaced ahead of a longish journey.  Better safe than sorry as I did once have a tyre with good tread blow on the motorway - terrifying!

My tyre with the issue were made Apr 16 the other front Nov 17. The Nov 17 one has a slow puncture so no point in getting fixed might as well have a new tyre

fatbelly

I think about replacing tyres after 6 years but I see the premium manufacturers are saying theirs are good for 10

avantra

I looked in our local tyre shop (a big independent), and I must say tyre depth on new rubber is all over the place.

Some examples I came across using my digital depth meter:
All-season tyres from Rotalla, Hankook, and Nankang have a similar grooving to the Michelin all-season Cross Climate model, but the outer grooves are at 7mm while the middle channel is shallower at 5.8mm, the Cross climates were 6.8mm in all grooves.

On summer tyres, Yokohamas were 7.5mm all round, while Bridgestone was 7mm all round.

Matador was 8mm, as did Kormoran and some Chinese tyres called Winrun.

So, for an all-season tyre with a shallower middle groove from new, how do you decide when to change when assuming you wear these evenly? Your outer groove will be at 4.5mm while your middle is around 2.1mm?!

This shallower middle groove is there by design, so where does the law-abiding driver stand if they have to buy a tyre with a usable 3.1mm?

Car_54

avantra said:

So, for an all-season tyre with a shallower middle groove from new, how do you decide when to change when assuming you wear these evenly? Your outer groove will be at 4.5mm while your middle is around 2.1mm?!

The outer groove is irrelevant. The 1.6mm legal minimum apples across the central 75%.