Older Tire Questions

I think how you drive the car would have some impact as well. ...that said, the industry standard is 6 years. If you drove it more sedately without spirited cornering...perhaps 8 years might be okay. (outside appearance doesn't tell you what is going on internally with the tire)

I notice that after 5 or 6 years, new tires make an amazing difference in ride and handling. The rubber gets ridiculously hard over time, but is hard to detect because it happens so gradually. Put fresh tires on, and instant improvement is noticed.

Since metric tires are made so infrequently, you have to be super careful to find out the manufacturing date codes before ordering.

 

Tires for high performace cars should never be used more than about 3 years. There is a noticble degredation in the grip and safety of the tires. I can tell the difference after 1 year of use. After a lot (40+) heat cycles the rubber just isn't the same. As the rubber hardens it becomes progressively easier for the rubber to delaminate from the belts and cause blow outs, vibrations, handling issues,...

For lower performance cars, the tires are 'safe' (in a DOT sense) for 6 years and should be replaced afterwards.

The solution to metric tire availability is new wheels of conventional size.

 

I learned my lesson- blew 2 tires (different days) on 8 yr old tires. Was doing 70. Good thing it was an Italian car- low to the ground. In a stupid suv (thats what the s stands for), would flipped and died.

Deceiving thing was the tires "looked" great! No cracks/no faded rubber look. Very deceiving. Beware, people.

 

It doesn't matter how "good" the tires look. Thirty year old tires can look good, but be ready to self-destruct. My feeling is that tires that are more than 8 years old should be replaced, especially on a high performace car. And if tire performance degrades enough to be noticable, I would replace the tires even if they are less than 8 years old.

When we buy helmets for the track, and someone is worried about the price, we ask "how much is your head worth?" Same thing is true with tires -- how much is your car and your life worth? New tires are cheap insurance that you won't have a problem at 60, 70, 80 or more mph.

 

Word.


Kai

 

I like the suggestion that "oh, no, my tires are heat cycled and getting harder, they're unsafe!" Of course, that would make every Toyota on the road unsafe off the lot.
No, I will not entertain further defenses and protestations.

At the the auto manufacturer I work at some very smart people did a lot of expensive research into tire aging. The guy in charge of it told me that the official recommendations (7 years?) are of the lowest common denominator variety; that's your number in hot environments. You'll go a lot longer in [probably all instances, actually] cooler locations, but, just like oil change intervals, these things are simplified for mass consumption and easy comprehension.

It is accurate that the tire degrades invisibly.

 

I agree. Thats why I say old tires that "look" good can be deceiving. Beware.

 

If your tires are getting old before you wear them out, you are not driving your car enough and are not driving it properly....IMHO.

 

Technically, 6 years is the 'safe' limit. Over that, it is like buying a cheap helmet. How valuable is your head?
I have seen tires blow out at 30 mph, no lie.

Regards, Alberto

 

Older tires get hard and you notice it when driving over small bumps. Nothing like a set of new tires. Regarding sizes, you just have to go for the next best available size and things should be fine.

 

LOL! So, how far did that car skid?

 

Generally when a tire does blow out the driver needs to be careful how he stops to prevent loss of control.
Applying the brakes can cause a weight transfer to take place and as the tire collapses the vehicles inertia will move in that direction.
There are several things the driver can do to help prevent a rollover ( although there is no guarantee that it won't happen) 1. Never apply the brakes, hold the steering firmly and if it feels like you are losing control, accelerate slightly. Allow the vehicle to slowly slow down.
Another approach is to depress the clutch, in this manner you are disconnecting power to the drive wheels, in this way the engine won't be able to "power" you into a skid.
Tire maintenance is an often overlooked area on a car, things that you should check weekly are: inflation pressure/tire cold,vehicle unloaded. Tread depth, 4/32 is good, less than 2/32 is marginal.
Look at all of your tires, they all should look the same, if 1 or 2 tires looks different than the others, you may have issues in several areas such as alignment, balance, worn suspension components etc.
A service technician can perform an inspection for a nominal fee.
I like to think of that Michelin commercial where the baby is riding on a tire.

 

Scary! Just a few years ago, I touched 125 MPH in some 17 year old Pirellis, just before replacement. Sad, those tires had less than 100 miles on them, heat cycled daily in the attic. They became really hard. Easily, flat spotted them on braking. I still have the Pirelli tires, now I am afraid to use them at any speed.

However, suppose I am a bit of a risk taker. Decades back, I touched 100 MPH in a Corvair. Also a short cruise at 140 MPH in a '65 Pontiac GTO, scares me to think about those tires. Also, the tread came off an E-Type Jaguar at 100 plus. I thought it was the sheriff helicopter on top of me, that I had spotted earlier.

You should hear motorcycle guys talk of tires. They replace tires frequently, as religion.

 

Not far, just very loud, thought I'd gotten shot at.

The whole sidewall had separated.

Regards, Alberto

 

Well, I guess Coker is getting ready to make $3000 on me.

 

Check Longstone Tyre in the UK. They were considerably less than Coker for XWXs I bought. And they had free shipping to US.

 

My experience is that it is braking that is most affected by age. The tires look fine and since they are all aged handling balance is not affected. But step on the brakes hard and the tires lock up very easily and generate little braking force.

It also depends on the tire. I have street legal race tires on my Abarth and they are still very soft despite being 6 years old. (I didn't ask about the date of manufacture when I bought them-- lesson learned.)

 

Especially old Michelin X series are very dangerous when they age, not sure about the XWX but possibly identical. I had a blowout at 70mph in the rear on a BMW E24 6 series with such X Michelins, and later I was told that those tires are known for that. It felt like the driveshaft was about to fall out, but it turned out nearly the whole sidewall on the left rear tire was gone. The car still handled pretty well though. I probably would have been less lucky if the blowout would have been on the front.

Then again I drove for years with my E9 CS on Dunlop SP Sport D3s that the DOT code did not even make sense on. They could have been 20 years old, and were probably older than the X's, but handled very well in the dry and stopped the car well. Wet not so much, but I avoided wet as much as possible anyway. The car never felt unsafe and I did far more miles and abuse on these tires than on the X's. Mind you, these tires spent most of their lives inside, contrary to the X's and as such had less exposure to elements.

Any speed has its risks, in any vehicle. New things ar not failproof, either. I believe if you use common sense then the risks are limited with older tires. I would not have for a minute wanted to try to break any speedrecords on those Dunlops though, and I took them off when I noticed that tiny cracks were beginning to form. I would relate the change interval to usage, UV and salt (!) exposure, crack formation and reputation, and a bit of fear factor. I would not take any tire beyond 10 years anymore, though - and far less if the rubber shows early ageing or it's not a good brand.