Clarification on if MOT failed and liklihood of tyre failure.

tedted

rubbish   

AdrianC

dave_long said:

Hi,
In April 2019 I received advisories on all of my tyres stating slightly damaged/cracking or perishing. I have driven the car only 4500 miles since. I have checked the tread depth with a 20p coin and all tyres are satisfactory across their widths

Maybe a stupid question ........ is it possible that tyres could deteriorate in 4500 miles such that they may become a failure now? In my eye there is no obvious damsge/wear and tear.

The actual test criteria is very well defined. The tester can only fail for...

"When assessing cuts in a tyre, it is permissible to check whether a cut is deep enough to reach the ply or cord by using a blunt instrument to open the cut taking care not to cause further damage. The following criteria should be used when assessing a cut in a tyre:
any ply or cord that can be seen without touching the tyre - fail
if by folding back rubber or opening a cut with a blunt instrument, so as not to cause further damage, exposed ply or cord can be seen irrespective of the size of the cut - fail
if a cut which is more than 25mm or 10% of the section width whichever is the greater, is opened with a blunt instrument and cords can be felt but not seen - fail
Before failing a cut, you must make sure it’s the cords that you can feel not a foreign object. If you’re not sure, then you should pass and advise."

"(d) A tyre:
(i) with a cut in excess of the requirements deep enough to reach the ply or cords - Major
(ii) with a lump, bulge or tear caused by separation or partial failure of its structure, including any lifting of the tread rubber or with cords exposed or damaged - Dangerous"
https://www.gov.uk/guidance/mot-inspection-manual-for-private-passenger-and-light-commercial-vehicles/5-axles-wheels-tyres-and-suspension#section-5-2-3

Whether it's wise to continue driving on tyres that you know are cracked and perished is another question entirely. Even superb tyres are cheap, when you look at their per-mile cost compared to your fuel cost.

Mutton_Geoff said:

Some MOT stations are more enthusiastic about this than others. What year were your tyres manufactured (four number week/year code on sidewall)?

Irrelevant. Tyre age is not part of the test, and testers cannot be "more enthusiastic" given the detail in the test criteria.

Scrapit said:

Mileage is not relevant in the case. Is there perishing and cracking on the tyre? Go look with a mk1 eyeball.

Indeed. That's all the tester does.

roddydogs

"Only 4,500 miles, lol"

Scrapit

Everyone is getting very excited and posting some euthisatic but irrelevant stuff. I stand by my post, have a look. If they ain't cracked then they will be ok. If they are then they aren't ok. Literally as simple as that. No skill, no mechanic, no tools, no training, no qualifications required. It's binary, cracked or not.

MinuteNoodles

Scrapit said:

Everyone is getting very excited and posting some euthisatic but irrelevant stuff. I stand by my post, have a look. If they ain't cracked then they will be ok. If they are then they aren't ok. Literally as simple as that. No skill, no mechanic, no tools, no training, no qualifications required. It's binary, cracked or not.

This is not true. A few years ago we had a camper van and all the tyres looked OK on that. Plenty of tread, no cracking at all, nothing untowards. One day when the wife was driving home in it one of the sidewalls let go, fortunately she'd been slowing down for a roundabout at the time. Looking at the date code the tyres were well over a decade old. They'd passed MOTs, they looked fine but just failed because of age.

Car_54

MinuteNoodles said:

Scrapit said:

Everyone is getting very excited and posting some euthisatic but irrelevant stuff. I stand by my post, have a look. If they ain't cracked then they will be ok. If they are then they aren't ok. Literally as simple as that. No skill, no mechanic, no tools, no training, no qualifications required. It's binary, cracked or not.

This is not true. A few years ago we had a camper van and all the tyres looked OK on that. Plenty of tread, no cracking at all, nothing untowards. One day when the wife was driving home in it one of the sidewalls let go, fortunately she'd been slowing down for a roundabout at the time. Looking at the date code the tyres were well over a decade old. They'd passed MOTs, they looked fine but just failed because of age.

But any tyre, of any age, can suffer a blowout. Not all defects are visible on the surface. And of course not everyone inspects the "wrong" side of the tyres.

Scrapit

MinuteNoodles said:

Scrapit said:

Everyone is getting very excited and posting some euthisatic but irrelevant stuff. I stand by my post, have a look. If they ain't cracked then they will be ok. If they are then they aren't ok. Literally as simple as that. No skill, no mechanic, no tools, no training, no qualifications required. It's binary, cracked or not.

This is not true. A few years ago we had a camper van and all the tyres looked OK on that. Plenty of tread, no cracking at all, nothing untowards. One day when the wife was driving home in it one of the sidewalls let go, fortunately she'd been slowing down for a roundabout at the time. Looking at the date code the tyres were well over a decade old. They'd passed MOTs, they looked fine but just failed because of age.

I'd suggest it was under inflated for some reason in that case.

AdrianC

MinuteNoodles said:
A few years ago we had a camper van and all the tyres looked OK on that. Plenty of tread, no cracking at all, nothing untowards. One day when the wife was driving home in it one of the sidewalls let go, fortunately she'd been slowing down for a roundabout at the time. Looking at the date code the tyres were well over a decade old. They'd passed MOTs, they looked fine but just failed because of age. 

Ancient tyres go hard, leading to harsh ride and sod-all grip.
They may also crack.

But if they aren't cracking, they wouldn't normally just blow out. And tyre age still isn't part of the MOT...

Mutton_Geoff

Scrapit said:

I'd suggest it was under inflated for some reason in that case.

I agree, or even internal damage caused by poor parking on a kerb. I often see cars parked with a tyre badly distorted against a kerbstone. Usually the same ones as have all the alloys scuffed ;-)

just_trying

It's not just the outside of the tyre to check, they obviously need replacing just do it or be stopped and if they're not good take your 3 points per tyre!