safulop

OK for all you participating,

I checked the date on my tires, the rears say 32nd week of 2012. They were installed in around April of 2013, so, pretty normal stock shelf life there. Yet, these tires appear to be ancient, and work that way.

Now as to the swerving, I did not have my foot still on the gas; I got sideways and let off the throttle, and then spent the next block or two swinging back and forth from one sideways direction to the other, at least 5 times back and forth before she would settle down. This was all with zero throttle, basically traveling at a forward speed of perhaps 15 mph. It was as close as you could imagine to just spinning out, without actually finishing the spinout. I never imagined something like that could happen, to be honest. I've certainly never done it before!

RKD in OKC

Found the higher the treadwear rating on tires you put on a sports car, the shorter their lifespan actually is. Think it is because the are harder and spin easier to start with.

Some tires more than others the exposure to UV is killer for making them hard and dry out. Usually you start seeing cracks in the sidewalls. Then it's really time to park it until new rubber is put on. You don't want to be driving when the start coming apart.

Also despite me not liking the overly shiny look of tired dressing, it help protect against drying out.

Have also treated tires with WD-40 to keep tread sticky down to past the tread wear mark on low treadwear rated tires.

Bought a one owner 92 Range Rover for a winter beater. I came with a set of tires. According to the date codes the set of tires it came with were the originals and the tires that were on it were put on right after purchase. This was a 92 in 2012. The truck had wintered in an the tires were stored in a hangar. After a year the sidewalls on the tires that were on it started showing cracks and soon after on of them came apart except for the steel belts (heard the air coming out and was able to get to the side of the highway before the actual blow out). Put the orginal 12 year old tires on which looked good and were great for the rest of the time I had the truck. Always parked in a garage. Glad the original tires were stored in a cool dry place in the dark!

safulop

I don't know, but I originally bought a set of Dunlop Direzza's for this car back in 2011. Now those tires were soft and sticky, and as a result they wore to bald in two years. Following which, Dunlop delisted them for use on the 928, since they decided they didn't meet the load requirements. No wonder they wore out so fast! I miss those tires, though, I used to call them my poor man's traction control. Virtually impossible to spin, in my automatic.

FredR

My experience is that quite the opposite seems to happen in that the softer the rubber the quicker they go off- why I do not know. I ran with Michelin Cup tyres for a while but after about a year they just seemed to lose their phenomenal grip altogether. Perhaps our hot temps play a role in the heat cycling process? That being said you chaps in the States can see temps close to or equal to what we see in summer.

For sure UV does for tyres thus why they are supposed to be stored in a dark place whilst on the shelf. A one year gap between when the tyre was made and when it was actually fitted is not t all unusual. Over here where tyres have a reduced lifespan there is talk that the police are going to declare tyres illegal if they are on the car more than 4 years after the date stamp.

Once the tyres do let go the fish tailing effect is what tends to happen if you come off the throttle once the back end lets go- possibly a combination of the initial reaction and then the natural counter reaction with the steering wheel as you try to bring things under control. I have had this happen a few times when on tyres that were due for replacement due to heat degradation.

Whether same would have happened had we stayed on the gas I do not know but the natural reaction is to come off the gas and that likely induces lift off oversteer and off you go [ask me how I know]. I put this down to the quirky behaviour of the automatic that possibly does not know what is actually happening and thus cannot work out what to do next thus why I do not like the automatic transmission on the track. To be fair it copes very well but there are limits as to what it can do for you and in my case at least that was with the PSD system.

No idea what happened to the OP's rubber to go like this. Falken may not be the best of tyres but I have not come across anyone flaming them at all.

Rgds

Fred

Adk46

I've been reading up on tires lately, how they are made, what compounds are used, what else is added (that was a shocker), and degradation mechanisms.

Degradation mechanisms include oxidation, UV and ozone. Clearly, the rate of degradation will vary tremendously from car to car depending on temperature, exposure to sun, and the amount of ozone in the air and ozone sources in your garage. And, of course, what the tire is made of and how it is used. And who knows how well the manufacturing process is controlled.

I don't like anything so simplistic and conservative as a simple expiration date representing the worst case; my tires live a best-case life.

uraniummetallurgist

Yes, ozone is a big problem for rubber. If you have an air purifier system in the house that generates ozone then that could explain your rapid tire degradation.
Best to check rubber belts and hoses as well under the hood.

hacker-pschorr

Ding Ding Ding Ding!!!!!! We have a winner.

I've been an advocate of replacing tires due to age / visual condition and feel over tread depth all my life. I got laughed at by people driving around on hard, cracked tires because "Lincolns head is still buried in the tread!!"

The Paul Walker incident is sending shock-waves through the auto forums with threads touting: "All tires should be trashed every 5 years!!!".....um, no. Not even close. I'm not disagreeing with the theory on the tires worn by Walker's GCT. In fact, the evening I learned of his death I said to my wife something about the tires being original. What shocked me is how long for that "theory" to get out to Gen Pop.

To add to what RKD said above, the car is also a huge factor. I bet if anyone took the tires off Paul's CGT and installed them on a stock 928 (pretend they fit) they would have been perfectly fine. 10 year old super soft compound (when new) rubber installed on a 605hp 3,000lb car with no driver aids....it's a recipe for disaster. I'm making huge assumptions here, who knows, maybe that car was stored in iffy conditions and the tires were dry rotted 8 years ago like the Falken's safulop has. I'm just trying to get a point across.

Bottom line, inspect, inspect, inspect. Properly storing tires can be tricky for a lot of people. I'm lucky, my basement is huge and a perfect place to keep tires, so is my climate controlled garage. The Michelin's date stamped 2008 on my 87 still look like new (except for slightly less tread) and even performed great in the rain a few weeks ago.

For the people stuck on replacing X years really think Jerry Seinfeld, Jay Leno etc... are replacing tires due to age??? Not a chance. I'm willing to be the tires on Jay's Countach are 12+ years old and yes, he still drives it. I'm making that assumption since tires in that size haven't been available for quite some time (there is talk of a production run starting up soon along with vintage P6's for Porsche's and other Lambo's).

Go to a car show or Cars N Coffee and check any car 10+ years or older the date stamp on the tires, what you discover may shock you. I know the owner of a 2004 Corvette still on original tires with less than 2k miles on them. This car has a more pampered life than the Queen of England. Mutual friend drove the car, decided to "give'er" for a bit and was shocked how well the tires hooked up (he's an accomplished track driver, not something I would have tried in this car myself).

So like anything, educate yourself, check the sate stamps, look closely for cracks etc.... if you are a very aggressive canyon carver, then yes, maybe replacing tires after 4-5 years just to have fresh sticky rubber is the best option for you. To the average drive, what you need to be conscious of is older tires will start to show their age on cold days, any moisture etc.... Just be careful and know what your car is riding on.

Friend of mine just bought a set of Goodyear's and bragged: "They are guaranteed for 8 years or 100,000 miles!!!"

Adk46

Someone should sell a simple device that measures the "softness" of rubber (modulus of elasticity, to be precise), and perhaps something that correlates with hysteresis/damping/tan-delta. A strap, a plunger mechanism, force/displacement gages, whizbang electronics.

Tire shops would love it - "Are your tires too old? Free tire check". Maybe it already exists.

FredR

Curt,
As per my earlier post- a little tug on the mould flashings tells quite a lot as to whether the tyres are serviceable. Beyond that a close look at the shoulder of the tyre gives a few clues if there are any signs of cracking beginning to appear. The available grip is also a tell tale sign but that is more difficult to sense as one grows accustomed to the progressively reducing grip levels available.

I dare say there will be a tool available somewhere that measures the rubber condition. I understand there are some compounds that the track guys can "paint" on the tread to help retain suppleness but whether they are practical for daily road use I have no idea.

Rgds

Fred

Imo000

How cold was the pavement?

safulop

Yeah, lift-off oversteer was certainly a problem in this incident, but when you're completely sideways in the traffic, it is hard to figure out actually staying on the gas. I mean, the initial oversteer was caused by overpowering the crap tires.

Road conditions were sunny pavement, about 68 F outside. I shudder to imagine running these tires in the colder weather. The new Pirellis should be arriving soon.

RKD in OKC

My 90 GT suspension setup provided power oversteer, lift off oversteer, and braking oversteer. BUT it sure was quick around an autocross course because of it! You were forced to use the steering wheel to keep it going where you wanted.

Jherriott

Greg, you really do make me laugh!

Like... people rise out of their cubicle and stare, sort of laugh.

(If i had a cubicle).

Jase.

safulop

I snapped a pic of the tire shoulder, you can see all the little cracks and how the tread surface seems excessively hard and almost shiny. Like, in a bad way.

This car lives in Fresno, in a non-airconditioned garage. This means it is subjected to 100-degree heat for several months every summer. Also the air here is horrendous, a notch down from Shanghai. So this is what Fresno air in a drought has done to a set of tires in 4 years.

Drewster67

Rule of thumb. You see cracks, replace the tire regardless of time stamps.