[Shiny]

Originally Posted by OCMDGTO

... The tires that came on my 20 Silverado (brand new) had to be replaced last year due to the same cracking that resulted in unfixable slow leaks. They don't make them like they used to.

I was similarly disappointed - had to replace tires on 2018 Silverado with only 20K miles. Same symptoms.

[chiphead]

Depends on a lot of factors. Cheap walmart tires in Arizona, 3-4 years tops. Michelins in a mild climate and maintained well, likely 8 years if they don't wear out first. Usually I wear out a set of tires in 3-5 years.

I bought a set of Nexens for my 2004 Silverado.. After about 2 years I parked it with 20K on the tires. It sat for a year with light use, then my cousin borrowed the truck for 6 months when his car died. After 2 months of commuting, every tire shifted belts. All 4 had wires poking out of the sidewall! Letting tires sit seems to be really bad for them, especially cheaper brands. The truck previously had worn out multiple sets of Michelins, at about 60-80K miles a set. These Nexens didn't last 25K with easy use.

Even a garage queen should get tires every 10 years. My 54 Bel Air project is sitting on a set of 21 year old cheap tires, with very little mileage and been out of the sun. They hold air and are good for moving the car around. But the sidewall cracks are easy to see, and I wouldn't trust them over 20 mph. When that one gets restored, it's getting new tires.

10 year old tires that sat for 3 years? I'd only run them... on a kid's tire swing! I find that kids don't want a tire swing if the steel belts are poking them.

[Schurkey]

Originally Posted by 79firebird_99TA

What is the general rule when it comes to longevity of tires?
The Firebird has been in the shop for the last 3 years and I'm looking to put it back in action this weekend. The tires are Cooper Cobras. I don't see any bulging or dry rotting. They're probably 10 years ago.

Thoughts? Run em?!!

Tires last fifteen minutes, or fifteen years. Depends on how they're used.

The tire industry has some *insane* recommendations, clearly designed by product-liability lawyers not engineers.

1. Best tires on the rear, not the front (including wrong-wheel-drive cars where the rear tires do nothing but keep the back bumper from dragging on the pavement.
2. Tires need to be replaced after five (or ten) years regardless of condition.
3. Tire repairs need to be hyperexpensive, and must include the tire being removed from the wheel

The front wheels do all of the steering, most of the braking, and all of the forward propulsion on wrong-wheel drive cars. Best tires to the front, and beware of--but not paranoid of--oversteer on low-traction surfaces. I've run tires that are far older than ten years; my friend is running tires on his 2-ton work truck that are decades old. I've used the D-I-Y Safety-Seal "worms" to seal punctures, and they work just fine.

https://www.amazon.com/Safety-Seal-L...dp/B0080IJYVK?

Big surprise: The tire industry provides "recommendations" that are self-serving, high-profit, and prey on motorist ignorance; while being "defensible" in court especially if the jury is uneducated in motor-vehicle dynamics. I have an unproven suspicion that modern rubber compounds--in particular from the bottom-feeder import brands--are deliberately designed to degrade so the consumer has to perpetually buy more new tires. This applies to tires, to windshield-wiper blades, and rubber products in general.

[HWYSTR455]

Here's NHTSA's stance on the subject:

https://www.google.com/url?sa=t&rct=...q&opi=89978449


If you don't want to read it, it states manufacturers suggest max age in the 6-10 year range. My personal tires I go no more than 5-7 years old, but rarely do they wear that long in my use. And I don't care what they look like.

Rubber breaks down over time and can compromise the construction/structure of a tire. The older they are, the more risk there is. Manufacturers know the construction and type of compound used, and probably are well aware of what the limits are. It's not an exact science, there can be tolerance variations during production.

I've been on 2 power tours, and the number of people who had tire issues were the number 1 cause of people dropping out. I see people on the side of the road all the time with flats etc on the way to the beach, not just collector cars. Those people usually only drive around town, short periods of highway use.

Even at 45mph, when a tire comes apart, you can lose control. Even if you maintain control, if it separates, it will beat your fender/quarter to a pulp.

Classic cars are not cheap anymore, even in 'restorable' condition they are generally over 20-25k. Many are attached to their' cars because of how long they've owned them.

If you know the risk, and you accept it, then it's up to you if you replace them or not, there's no law that says you have to. But if something happens, there's no one else to blame but yourself.


.

[grivera]

The state of Maryland requires a safety inspection for all cars registered in the state at the time of title transfer- it’s a one time occurrence. They measure brake linings, ball joint wear, windshield, tire tread, etc. It’s one of the most comprehensive inspections I’ve seen. While tire condition is checked, interestingly enough tire age is not on the list. With the litigious society today, this really surprises me considering the date codes are easily found and how vulnerable we are driving on old tires that look perfect but may blowout at any moment.

[JLMounce]

My BFG Sport Comp II's needed replacing at 7 years due to tread delamination. They had about 60% of their useable tread life remaining.

Depending on how the tires have been used and stored anywhere from 6-10 years is probably your window of replacement, even if there is good tread showing.

[Skip Fix]

You just have to ask yourself is it worth the risk of tearing up the car or worse case crashing at speed? If your car is trapping 100 mph -not too hard-and you have a blow out

Kind of like trailers. I used to borrow a buddy's utility trailer for my car to go racing until one day hit some grooved pavement that got it swinging and barely could slow it down to stop. A 42K dedicated car trailer was worth it not to crash!

[79firebird_99TA]

Definitely not enough burnouts on these. I know the pics don't indicate the condition of the tire ... but I'm gonna run them for now

[Rachelsdad]

This thread reminded me of Jay Leno's piece in Hagerty from over the summer:

https://www.hagerty.com/media/opinio...ut-1200-tires/

Indeed, a number of factors come into play with how long tires may last (quality, exposure to UV, driving habits, general road conditions, climate, storage, care, etc.).

In 2005, I purchased a set of Diamondback radials for my '63 Bonneville. The car was in the shop at the time for a frame swap, and stayed there, out of the sun and off the road, until this past November. These tires look and feel like brand new. Surely, the rubber itself has aged somewhat, but not to the extent it would have had the car been driven (at all) or left standing outside in the daytime exposed to UV. (So far, they have a grand total of about 150 miles on them.)

My daily driver is a 2006 Cadillac STS-V. These cars came from the factory with Pirelli run flats which everyone hated. When I got my car in 2021, it already had Continental Extreme Contacts on it. These are amazingly soft riding tires (not run flats) with excellent grip and handling characteristics. However, I've had to replace every tire on the car for various reasons, despite them all being relatively new when I got the car (sidewall separation, sidewall damage from a nail - yeah, just past the tread line - etc.). I'm in the northeast, so winter weather is a factor. I keep them inflated to about 36psi (air, not nitrogen, so they do expand and contract). I don't expect these tires to last 5 years, even if I were to reduce the miles I put on the car every year.

In short, any of these "tire life guidelines" are simply that: guidelines. Every model of tire is different, every car is different, every road is different, batches of tires are different, UV exposure differs...there are just so many factors to consider that at some point, personal preference and experience has to be taken into consideration.

I will be driving on my Diamondbacks on the Bonneville to Arkansas from New York this year, and I have no concerns about the drive. (Prior to this set of tires from 2005, my Sears GR78-14's dated back to about 1977, and served me well - LOL.)

[triathlonx13]

My rule - 6 years max for daily drivers, trucks, trailers.

[Terry M. Hunt]

Very timely post since I’m looking at 4 cars that have tires approaching 10 years. I get very paranoid imagining all the carnage that a tire failure can create, but the cost of replacing four sets of radial redlines at once is damn intimidating! Maybe I’ll have to take 3 out of circulation until I can address them one at a time

[Cliff R]

Rear tires on any of the musclecars I've owned don't last but a few hundred miles. I was lucky to get 50-60 runs out of a set of Mickey Thompson Drag Radials when I switched to those for rear tires. So I never had to worry about dry rotting or having problems with them do to the age.......

[78w72]

I think it was mentioned earlier about the safety regulations or tire companies not touching tires older than 5-7 years, thats more for liability concerns than actual age. Kind of like how some say braided hose needs to be replaced after 5 years, i have & know of lots of cars with braided hose thats 10+ years old that still works fine with no fuel seepage or leaks. Or the 3000 mile oil change, very rarely does oil go "bad" after just 3000 miles in a healthy engine, the oil companies want you to buy more oil. Lots of things do that, home washer hose replaced in 3-5 years? There are millions of houses with 10-15+ year old washer hose. yes anything can happen but just like lots of things, the odds are very low that any item will fail when the manufacturer or safety people say they will.

I have tires on some of my cars that are 10 years old but look great with no signs of cracking, belt slippage etc, they all get stored for 4-6 months a year in winter & never have flat spots, usually BFG T/A or firestone indy 500.... but then again I dont daily drive these cars & rarely if ever spend any real time on the interstate at 70+ mph, they are city drivers or back country roads. If i planned a long trip or drag strip use they would get changed or use different tires dedicated for the purpose.

However, the reality is that there are millions of tires that are easily 6-8-10+ years old on the road and catastrophic tire failures are very rare statistically speaking. While I agree its good advice & you should definitely inspect or monitor your tires when they get that old, but its not an automatic thing to change tires if they have decent tread & in good condition after 5 years. If anyone is doing that on 60+% tread 5 year old BFG's or other name brand tires, I will take them & pay for shipping. Lots of burnouts left in them.

[HWYSTR455]

I just replaced the tires on the judge project, they were 7 years old and had less than 1000 miles on them, looked perfect. I should have kept them for anyone who wants to take chances.

My bird project has been sitting for 20 years, has a never driven on set of Nitto 555s. It's in paint jail right now, ready to be sprayed. When that comes back home, I will have a set of tires for those people who are 'braver' than I.

Watch my build thread in the 70-73 section for when that happens, and PM me.

(I will try to limit my posts when I've been drinking!)


.

[burd]

On the way to get an ice cream, let it blow. lol I got a spare nos rim
And if it blows at Dream Cruise, more people will get to see your car in the traffic jam. Jam.

[65madgoat]

If age was not an issue, some track day events would not have limits like tires can not be over -3- years old.

If you value your car and your life, get fresh tires. Silly to run any tires that are considered by most as old because you think they still "look" good.

[Sirrotica]

The bonding of the rubber to the steel belting is what does modern tires in. When the bond starts to be compromised is when the parts inside start delaminating from each other.

The Firestone debacle years ago was said to be due too the fact that the materials that the steel belting were made from, were stored outside. Rust started on the steel cords, and that made the bond of the rubber to steel was compromised from the beginning. No one can look inside of a tire after manufacturing to see if the steel to rubber bond is compromised, so there is no way that eyeballing the outside of a tire can determine if the core parts are breaking down. This is the reason that some people can run tires for 15 years without incident, and others fail internally at 5 years.

Radial tires are much more suseptible to belt failure than bias ply tires are, due to the angle the belts are in relationship of each other. The belt angle is also the reason that the old bias ply tires could have sidewall punctures repaired, and radials can't have sidewall repairs. The fact that radial belts don't criss cross in the sidewalls, makes the sidewall rip from the bead to the treads, ending the life of he tire.

That's how I understand the reasons given by manufacturers for radial tire failures, YMMV.

[78w72]

I mentioned I would take 5 year old tires... not 20.

Never had a track day at my local track limit tires to 3 years old... in fact at tech, they dont even look at tires dates for street/strip type cars, not sure about the faster big tire cars or NHRA funny car/dragster events.

[Shiny]

Originally Posted by Sirrotica

The bonding of the rubber to the steel belting is what does modern tires in. When the bond starts to be compromised is when the parts inside start delaminating from each other.

The Firestone debacle years ago was said to be due too the fact that the materials that the steel belting were made from, were stored outside. Rust started on the steel cords, and that made the bond of the rubber to steel was compromised from the beginning. No one can look inside of a tire after manufacturing to see if the steel to rubber bond is compromised, so there is no way that eyeballing the outside of a tire can determine if the core parts are breaking down. This is the reason that some people can run tires for 15 years without incident, and others fail internally at 5 years.

Radial tires are much more suseptible to belt failure than bias ply tires are, due to the angle the belts are in relationship of each other. The belt angle is also the reason that the old bias ply tires could have sidewall punctures repaired, and radials can't have sidewall repairs. The fact that radial belts don't criss cross in the sidewalls, makes the sidewall rip from the bead to the treads, ending the life of he tire.

That's how I understand the reasons given by manufacturers for radial tire failures, YMMV.

Good info, thanks!

All the comments in this thread make sense to me, and I used to do the math to predict product failures. Fortunately, I never worked on stuff like tires where people could die if I was wrong.

The biggest mess with this stuff is the variation in time to failure across ALL tires a manufacturer ships is HUGE. For a tire, it would not surprise me that 1% will fall apart before 5 years and 1% would survive well past 20 yrs. Predicting the life for any single tire on any car in any climate with any driver, etc. is not going to happen as you have all discussed.

So yes, the probability for early failure may be low, but the consequences of a failure are what matters when either you or a manufacturer makes decisions about tire life.

A manufacturer is going to protect itself and set a line in the sand that may seem WAY conservative for most of us... but we aren't the ones getting sued if someone gets injured or worse.

I think the biggest takeaway for me is that internal tire failures are not always visible. Cracking on the outside is obvious, delamination or material degradation on the inside isn't.

And some of the new tires I've bought cracked in only a few years, which is frustrating considering their cost.

[carbking]

Gee, after reading this thread, thinking about buying a lottery ticket!

Bought new performance (non-Pontiac) in 1979.

One tire destroyed by debris in a parking lot in 1995.

Replaced the entire set to maintain tire diameter.

STILL using the car, AND the 1995 tires.

Of course, my feeling is that if the word "Michelin" is not on the sidewall, it probably isn't a tire.

Last blow-out was about 35 years ago on a used pickup that I had just purchased.

Been driving since 1962, that was the only blow-out; did have a couple of tires develop knots before I refused to buy anything but Michelins.

Jon