hi,
Common sense . Keeping the rubber rotating 5000kms per yr = approx. 10-15yrs . OR When side wall or tread cracks appear its time to replace if the tread is road worthy.
Remember lack of use also deteriorates rubber .
Wheel alignment as needed.
Wheel balance helps bearing life .
maintain brgs and tyre pressures.
Some tyres are 3yrs old when sold .!!

Look on the tyre for week & year it was made WWYY. 10 years is the maximum life of a tyre under idea care & no potential damage, but look at replacing it after 5 years. 

I check tyres daily at least when in the outback.

Recently helped a potentially stranded 4wd with rock through the tyre. 3 plug repair. Their spare was 10 years old & full of cracks & flat, in a modestly remote area.

If you value your & other lives put some new tyres on at 5 years.

I recently put two brand new but 5 year old tyres on my Hilux hoping to get a little extra from them. Both were well sheltered their entire life with no obvious cracks or bulges. One lasted less than 800km before a huge chunk was carved off by an abrupt edge of a pothole or road edge. Old tyres are brittle and no where near as flexible as new tyres.

A 2006 Michelin USA document:

The following recommendation applies to RV/Motorhome tires. Tires are composed of various types of material and rubber compounds, having performance properties essential to the proper functioning of the tire itself. These component properties evolve over time. For each tire, this evolution depends upon many factors such as weather, storage conditions, and conditions of use (load, speed, inflation pressure, maintenance, etc.) to which the tire is subjected throughout its life. This service-related evolution varies widely so that accurately predicting the serviceable life of any specific tire in advance is not possible.

That is why, in addition to regular inspections and inflation pressure maintenance by consumers, it is recommended to have RV/Motorhome tires, including spare tires, inspected regularly by a qualified tire specialist, such as a tire dealer, who will assess the tires suitability for continued service. Tires that have been in use for 5 years or more should continue to be inspected by a specialist at least annually.

Consumers are strongly encouraged to be aware not only of their tires visual condition and inflation pressure, but also of any change in dynamic performance such as increased air loss, noise or vibration, which could be an indication that the tires need to be removed from service to prevent tire failure.

It is impossible to predict when tires should be replaced based on their calendar age alone. However, the older a tire the greater the chance that it will need to be replaced due to the service-related evolution or other conditions found upon inspection or detected during use.

While most tires will need replacement before they achieve 10 years, it is recommended that any tires in service 10 years or more from the date of manufacture, including spare tires, be replaced with new tires as a simple precaution even if such tires appear serviceable and even if they have not reached the legal wear limit.

For tires that were on an original equipment vehicle (i.e., acquired by the consumer on a new vehicle), follow the vehicle manufacturers tire replacement recommendations, when specified (but not to exceed 10 years).

The date when a tire was manufactured is located on the sidewall of each tire. Consumers should locate the Department of Transportation or DOT code on the tire that begins with DOT and ends with the week and year of manufacture. For example, a DOT code ending with 0304 indicates a tire made in the 3rd week (Jan) of 2004.

Hey Whenarewethere,
I guess it also depends on what you Google and who you believe
From Tire Safety Group

Tires Expire in Six Years
The evidence is clear: tires should have an expiration date. Older tires are substantially more likely to fail than newer ones. This is because tires are made mostly of rubber, and rubber degrades with age. Sunlight, heat, ice, and general wear and tear can accelerate the breakdown of a tire. Once a tire begins to break down, it becomes more likely to fail in the form of a tread separationoften at highway speeds, when the failure is most likely to cause catastrophic injuries or death.
For most tires, this expiration date should be six years from the date of manufacture. Tires age dangerously because of a chemical process commonly referred to as oxidation, which simply means that as the tire components are exposed to oxygen, the oxygen particles cause the flexible components of a tire to harden and become brittle. Over time, the tire will simply fall apart under normal stress, just like an old rubber band. Because this process occurs naturally, it does not matter if a tire is being used, stored as a spare, or simply waiting on a store shelf for an unsuspecting consumer. 1
In 1973, the average tread life of a passenger car tire was approximately 24,000 miles. Tire tread life has quadrupled over the last forty years and some currently sold tires promise 100,000 miles of tread life. As tread life becomes less of a factor in the service life of a tire, oxidation becomes a more serious concern particularly in hotter climates, like Texas, Florida, Georgia, and Louisiana which are routinely the hottest states in the United States. 2

Tire Manufacturers Warn that Tires Expire in Six Years
Many auto manufacturers have taken small steps to warn consumers by placing warnings within the owners manual of newer model vehicles. However, due to the cryptic code tire manufacturers use on tires, the warnings are of only limited use to consumers. Nonetheless, the following manufacturers have issued warnings on 2013 and newer vehicles about tire aging:

Sadly, these warnings are not retroactively provided to consumers who own older model vehicles that are more likely to have aged or expired tires.

My expensive Pirreli AT Plus tyres are made in China like everything else so I won't be leaving them on the car too long if I haven't used them!

-- Edited by Whenarewethere on Tuesday 26th of March 2019 10:17:51 PM

dabbler wrote:

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Hewy54, Age *is* irrelevant mate. A near new tyre stored in the elements and subjected to environmental and mechanical extremes can fail very quickly, because it's condition is the governing factor. The time a tyre should be replaced is opinion and not a measurable characteristic. Why a tyre be replaced is easily quantified and measured. That's why laws are written in terms of condition not age. You can argue certain things paralleling age and condition but there is only generality and no consistency.

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 Yes it is opinion, but condition cannot always be determined by outward appearance.

Just have to agree to disagree on this one.

 

I change my van tyres at 5-6 years unless they are worn out before then. Having to throw away an unused tyre, causes me now to do a 3 tyre rotation (single axled van).
The 4wd - about every 2.5-3 years & by that time they've done over 50,000kms.

How the tyres are treated can make a big bearing on their life eg the spare on my car was always covered with a vinyl cover that was difficult to remove/replace. I found out why at my last tyre change - it was a larger tyre (275x16 instead of 265x16). Somewhere in the car's history someone must have fitted larger tyres.
The spare looked perfect - was ten years old, had been used but there were no cracks, irregularities on it. The fact it had been covered, preserved it. I now do a 5 tyre rotation of the correct sized tyres.

Thanks, to every one, My tyres are still looking in great condition, but age is getting up a bit, Contacted my insurer, they have no Year expiry, but as I had put in my
Post and they say Common sense comes into it. But at least I have found out they do not have a year limit on the policy.
Regards Bowser.

Peter_n_Margaret wrote:

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Tyres are not all the same, so to try and put a life on them all the same makes no sense.
Nor are they used all the same way.
In particular, some tyres are loaded to 90% or more of their maximum load carrying capacity. That will make a very big difference.
Mine are never loaded beyond 60% of their maximum load capacity.
Cheers,
Peter

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 I guess its the same as all maintenance on your vehicles. There are recommendations about how often you change the oil, but I would suggest that you modify this according to the usage. The word from the manufacturers on tyres is that due to the chemical construction, tyre may last between 6 and 10 years. I have had an excellent run out of my vehicles as I tend to err on the side of caution. If anyone wants to push the limits a bit more, go for it.

hi
One of the biggest killers of van tyres is lack of use . Mounted /inflated tyres prefer to be unloaded when stored but tyres still prefer tobe used a min amount.

-- Edited by swamp on Thursday 28th of March 2019 04:59:01 AM