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Tyre Age

PostPosted: Fri Sep 24, 2010 6:45 pm
by jonnyconcrete
Here's a thought...what's the consensus on tyre life in years...I have 13 year old tyres that have done 13k, they look brand new...but are they still safe?

Re: Tyre Age

PostPosted: Fri Sep 24, 2010 6:58 pm
by theelanman
as far as I know
:?
each tyre type/make has different construction/chemicals in so I would say it depend on what they look like........
I think they have a shelf life of about 4 years at the dealer then how ever long they last on your car.....but you should notice a drop off in their performance when theyre past it....
they go hard first and if you ever get caught in the wet theyre like slicks....
if theyve really gone then they would feel like ice driving on dry roads.....
then inspect them for rubber degredations and cracking in the side walls...once the rubber has lost its elasticity then the side wall will perish......

Re: Tyre Age

PostPosted: Fri Sep 24, 2010 7:14 pm
by Spyder fan
Do a web search and the first thing you will presented with will be a 6 year shelf life for tyres, thats a sort of automotive equivalent of a supermarkets food label use by date. We all know that just by using our eyesight, our sense of smell and a little common sense that that pack of cheese will still be okay to eat at least 2 or 3 weeks past the date but only if it has been stored correctly.

There's a very sensible article on the Michelin UK web site, you would think that they might have a vested interest in scaring us all witless into changing our tyres, but that doesn't seem to be the case and they give some sound advice. http://www.michelin.co.uk/connected/tyr ... e-my-tyres


Have a read of this and then apply your common sense to your tyres; if it were my car I would change them for new, they have given good service and have obviously been looked after correctly, but nows the time to change.

The reason that it's recommended to change your cambelt on a modern car after 6 years irrespective of the mileage on the engine is that the rubber in the belt loses its elasticity over time and the danger of it snapping increases greatly over time. It's noticeable if you drive your car hard on track days etc that 2 or 3 year old tyres are not a patch on fresh rubber even if the tread depth is similar, i would think that driving on your tyres is like going back to skinny crossplies on my first and much missed Mini..

Regards

Re: Tyre Age

PostPosted: Fri Sep 24, 2010 8:32 pm
by Galwaylotus
The real danger is what you can't see. Older tyres run the risk of delamination even when they look fine on the outside. It just isn't worth the risk and I would set 10 years from manufacture as an absolute maximum. Even that is only if conditions have been favourable. Car manufacturers advise replacement at 6 to 10 years. :shock:

Re: Tyre Age

PostPosted: Fri Sep 24, 2010 11:29 pm
by SprinTango
I posted a similar query recently, after buying some Elan wheels with unused tyres fitted to them. Based on the date coding these tyres were 11 years old, but looked brand new and were still flexible. Due to being low profile I did not want to keep the tyres and have just sold them on ebay. The tyre depot that removed them from the rims said "don't worry about the age, these are basically new tyres"
Obviously this would depend on how they have been stored over the years, i.e out of sunlight and not bearing any weight in the case of mine.
My mother recently gave up driving. Her last car was a 1996 Renault Clio, purchased new. In 14 years she did 21,000 miles, all on the original tyres. Each year the car passed an MOT without any comment on the tyre condition. Visibly they were not cracked or perished in any way. Again the car was garaged when not being driven, which may have helped.
At a car show last month I came across a JPS lotus Europa, very low mileage and recommissioned after long term storage. The owner claimed it was on it's original tyres!
Regards,
Nigel

Re: Tyre Age

PostPosted: Sat Sep 25, 2010 7:57 am
by terryp
The Caterham that I bought in April had done 9000 miles from new in 1985. The date on the tyres turned out to be 1982! So 28 years old!!!!!!!
The tyres look like new with no cracking or obvious degradation but to be fair seem somewhat hard.
I succumbed to opinion and have changed them, well not quite yet - Yoko A021's have arrived , they are going to be put on the rims in the next week.
I do feel however that I perhaps I didn't need to change them but who knows????????????
Its a shame there isn't some cheap rubber flexibility testing machine as I feel that the life span on tyres seems to be set by the tyre manufacturers themselves.
I have 12 year old tyres on the +2 which seem OK , so not being changed for the moment

Terry

Re: Tyre Age

PostPosted: Sat Sep 25, 2010 8:49 am
by RichC
going back a while I remember that my 1970 citroen DS Safari still had the original michelin XASs on the rear when she went to the great scrapyard in the sky 27 years later ( 'cos we looked into the datecoding on the tyrewalls) & they had passed 25 MOTs.
but then of course those cars were famous for being able to be driven with one of the rear wheels missing if I recall (never tried it meself)? & they had innertubes as well....

one of the guys who I met on trackday in summer had new tyres on his S3 which had thrown off chunks of tread after a few minutes hard cornering!

Re: Tyre Age

PostPosted: Sat Sep 25, 2010 9:29 pm
by Galwaylotus
From Ford's website:
Tyre Age
The general rule is that a tyre lasts 6 years. After this, it should be changed ? even if it looks like new and has hardly been used.
The age of your tyres can be found on the side wall. It?s a coded production date ? for example, in '0702', '07' indicates week 7 and '02' signifies 2002. Until 31st December, 1999, a '<' appeared after the third digit e.g. '8<' for the year of production 1998. If you discover such an old tyre, please change it immediately! Tyres older than six years should be replaced, and this applies to the spare tyre as well.


Research into the Causes of Ageing
Tyre rubber is composed partly of natural substances and is therefore subject to ageing. As a result, the technological properties of tyre materials change over time. Inappropriate storage can accelerate this ageing process. This is why a tyre should only be used in the six years following its production date. Despite anti-ageing additives used by tyre manufacturers, tyre materials are sensitive to environmental influences such as temperature, sunlight, humidity and ozone. Contamination through oil, grease, paint, fuel and similar substances must also be avoided.
Storing your Tyres
It?s very important to look after your unused tyres. Storing them incorrectly can shorten their lifespan considerably. If you would like to find out more about storing your tyres properly, download this PDF document.

Re: Tyre Age

PostPosted: Sat Sep 25, 2010 9:32 pm
by Galwaylotus
. . . and for our friends on the other side of the pond:

Should Tires Have an Expiration Date?
As recently shown on ABC news, seemingly "new" tires may have been manufactured many years ago. According to the report, if the tires are six or more years old, they present a hazard and should not be purchased. Old but unused tires may experience tread separation, causing the driver to lose control of the vehicle and possibly crash or rollover. The way to determine the age of the tire is as follows. A four digit number such as 2207 means the tire was manufactured the 22nd week of 2007.

Tires Degrade Over Time

Tire experts say tires degrade over time. The oils, chemicals, rubber and bonding all start to come apart as time wears on. If a tire is not used, it only speeds up the process, because there are certain chemicals used to protect the tire that are only activated if the tire is in normal use.

"Gradually it's been apparent there was this problem, but the industry nervously looked the other way, because the tire industry is very, very sensitive to anything that involves danger and their products," said Rex Grogan, a tire consultant who formerly worked for British tire maker Dunlop for 33 years.

Grogan supports the time limits set by the British Tyre Industry Council.

Warning Signs Are Not Always Visible

Often, there is no way to determine if there is anything wrong with a tire by simply looking at it. And tires may spend a substantial amount of time in warehouses and distributors before they even reach stores where they are available to consumers.

It's not easy for consumers to determine the age of a tire. It requires the ability to decipher the last three digits of the Department of Transportation number molded into the tire.

The first two digits correspond to the week of the year the tire was made and the third digit corresponds to the last digit in the year it was made. For example, a DOT number ending in 238 would have been produced in the 23rd week of 1998.

Michael Rotondo from Massachusetts just bought a 1993 Isuzu and was shocked to discover that his spare tire was 11 years old. "I think after work today I'm going to stop by the place I bought it and ask them for a new tire," Rotondo told ABCNEWS.

Re: Tyre Age

PostPosted: Sun Sep 26, 2010 6:26 am
by RichC
this seems like scaremongering to me !.
next thing we'll hear is that insurance companies will use this as an excuse.
i.e. you're not covered 'cos your tyres are too old .

replacing tyres every 6 years just to be on the safe side seems to be (IMO) rather wasteful



even new tyres can have blow-outs from contact with road debris.
My mini has runflats and the BMW design flaw with the tyre pressure monitoring system meant that although i had it from new and had it serviced on time I still ended up stranded one day 'cos the nsf tyre delaminated & fell apart.It lasted only about 10 miles after the warning sign alerted me rather than the guide of 100miles if driven below 40
the tyres always looked OK and the alarm stayed off meaning that the pressures were balanced .
It's only when i was recovered back that the tyreman placed a bet that my other tyre was equally flat ... it was giving just 15 lb/si

Re: Tyre Age - Just drive it!

PostPosted: Sun Sep 26, 2010 7:12 am
by gordont
As a thought perhaps if the cars were driven more often then the issue of typres would not be a concern AND the added benefit that you get to enjoy the car.

Off this week to get a new set of rear tyres, 12000 miles was the most I could get from the Dunlop D98J's over a 18 month period. :D

Re: Tyre Age

PostPosted: Sun Sep 26, 2010 7:30 pm
by Galwaylotus
This is the article I was seeking earlier. It's on the IVVCC website at http://www.ivvcc.ie/news.htm. Scroll down to the second article.

I believe it just isn't worth the risk to either my Elan or the possibility of injuring someone - or worse.
TYRES --- A WARNING!

The following article is reproduced courtesy of FBHVC (Federation of British Historic Vehicle Clubs), Newsletter 04-07. This is is a much-overlooked item of safety --- even by drivers who are fastidious about high standards. Many are not aware that tyres degrade with time and become unsafe; note the recommendation in red below. The FBHVC are to be commended for highlighting this issue. (Thanks also to Noel Doyle for bring attention to this article.)


Her Majesty?s Coroner for Manchester wrote to FBHVC just after the last newsletter went to press and many will have seen this topic on our (FBHVC) website - it is an important matter and we urge clubs to pass the warning on to their membership if they have not already done so.

The letter concerned an accident that took place last year in which the driver of an H registered MG B lost his life when a rear tyre burst on the M56. The driver was a skilled mechanic and a careful and experienced driver who was not travelling particularly fast at the time. The car was described by police as being maintained in excellent condition. The surviving passenger said that just before the accident the driver had commented that a ?tyre wobble? had developed and he was going to ?drive through it?. The wobble went briefly, but then the tyre burst, causing the car to spin, clip a kerb and flip over.

Subsequent investigation showed that although hardly used the tyre was 25 years old. It was one of a set of as-new tyres and wheels bought at an autojumble the previous year for use for show purposes (at the time of the incident the car was on its way to an event at Oulton Park).

This note appeared in the Newsletter for December 2003 following a suggestion that tyre dating may become a feature of the MoT: ?the Vehicle Standards and Engineering Division at the Department for Transport [has advised us] that although most tyres already carry dates of manufacture in their side-walls, there are no plans to implement regulations to check such dates at the annual MoT test. DfT would, of course, change their mind if tyre failure due to age became a significant cause of accidents.

The British Rubber Manufacturers Association suggests that if a tyre is six years old and remains unused it should not be put into service. It also suggests that in ideal conditions tyres may have a life expectancy of 10 years.

The moral of the story is not to wait for legislation, but to make sure your own tyres are in good condition, never to use undated or obviously old second hand tyres however good the tread and never to ignore a ?tyre wobble?.

The webmaster found the following helpful information published by the Vredestein tyre company:-

The sidewall of the tyre carries a code from which the production date can be derived. Since January 1st 2000 the production date is made up of 4 numerals, for instance

DOT 9D YE 2406
means that the tyre was made in the 24th week of 2006

From 1990 to 1999 these were 3 numerals with a triangle, for instance 4583

which in this example means that the tyre was made in the 45th week of 1998. If there is no triangle behind the three numerals, the tyres were made prior to 1990. Please check your tyres and if they are more than six years old you should consider replacing them with new tyres. Driving on tyres more than ten years old may expose a driver to liability for using unsafe components on his vehicle.

Re: Tyre Age

PostPosted: Sun Sep 26, 2010 7:46 pm
by summerinmaine
RichC wrote:this seems like scaremongering to me !.



I don't think that the warnings are scaremongering exactly, but I do think that the six year guideline is pretty conservative. One has to wonder what measures were used to determine that limit, or is it like the guideline for how much you should spend on an engagement ring, as determined by the deBeers diamond cartel? :roll: