Tire Service Life

[lfalzarano]

I heard/read in the past that tires get old and should be replaced after 5 years. I'm facing that costly project this year and did some more research. I have the Goodyear GS-D3's with plenty of tread and no wear, damage or cracking. Internet research found a TireRack article on the topic. It also includes several other tire manufacturer's recommendations.

https://www.tirerack.com/tires/tiretech/techpage.jsp?techid=267

Basically, Goodyear's latest bulletin from December 8, 2011 says,

"Tires are designed and built to provide many thousands of miles/kilometers of excellent service.

Tires are removed from service for reasons such as: (1) the tread wears out (down to 2/32nds of an inch) (2) road hazards damage the tire (3) the tire is run underinflated or overloaded and is damaged (4) consumer’s choice or personal preference.

Tire materials (including rubber) have performance properties essential to the proper functioning of the tire itself. These properties evolve as a function of time, service and storage conditions: it is a physical property of rubber that it changes with time. However, for each individual tire, the degree and amount of change is affected by many elements such as temperature, storage conditions, and conditions of use (load, speed, inflation pressure, impacts with potholes, etc.) to which the tire is subjected throughout its life. Since service and storage conditions vary widely, accurately predicting the serviceable life of any individual tire in terms of years and/or months is not possible."

So, if I don't have the above mentioned tire issues as described, should I refrain from replacing them until they exhibit those signs?

[Mr Blue]

i would replace the tires. A friend that owns a '93 C4 LT1 was drivng on original low mileage tires, doing some spirited freeway driving alongside a BMW when the right rear shredded. It was not a pleasant experience for him. Had to get new tires, repair the wheel, not to mention the white knuckles. older tire harden with age and are not trustworthy. Just my$.02.

David

[RussMcB]

It might depend on how much performance you require. If it's just rolling down the road to a car show, with the tires keeping cool and unstressed, they'd probably last for decades. But, if you need a lot of traction to avoid crashing, you'll want "fresher" tires.

[lfalzarano]

i would replace the tires. A friend that owns a '93 C4 LT1 was drivng on original low mileage tires, doing some spirited freeway driving alongside a BMW when the right rear shredded. It was not a pleasant experience for him. Had to get new tires, repair the wheel, not to mention the white knuckles. older tire harden with age and are not trustworthy. Just my$.02.



David



David,

Although mine only have very few miles and are nearing 5 years, I am worried I might do something more spirit in a moment or at a chatty track laps event. Rolling around town would be safe, but under stress you can’t predict until it’s all over. Thanks for the reality check!

Lou


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[DRM500RUBYZR-1]

Replace the tires.
:cheers:
Marty

[32valvesftw]

When I got my Z it had some old BFG tires on it, they had plenty of tread, no cracking or rot. Then I took a turn with more juice than normal and lost it. luckily no damage. Replace the tires soon. After new tires it is much harder to kick the tail out.

[Kevin]

I heard/read in the past that tires get old and should be replaced after 5 years. I'm facing that costly project this year and did some more research. I have the Goodyear GS-D3's with plenty of tread and no wear, damage or cracking. Internet research found a TireRack article on the topic. It also includes several other tire manufacturer's recommendations.

https://www.tirerack.com/tires/tiretech/techpage.jsp?techid=267

Basically, Goodyear's latest bulletin from December 8, 2011 says,

"Tires are designed and built to provide many thousands of miles/kilometers of excellent service.

Tires are removed from service for reasons such as: (1) the tread wears out (down to 2/32nds of an inch) (2) road hazards damage the tire (3) the tire is run underinflated or overloaded and is damaged (4) consumer’s choice or personal preference.

Tire materials (including rubber) have performance properties essential to the proper functioning of the tire itself. These properties evolve as a function of time, service and storage conditions: it is a physical property of rubber that it changes with time. However, for each individual tire, the degree and amount of change is affected by many elements such as temperature, storage conditions, and conditions of use (load, speed, inflation pressure, impacts with potholes, etc.) to which the tire is subjected throughout its life. Since service and storage conditions vary widely, accurately predicting the serviceable life of any individual tire in terms of years and/or months is not possible."

So, if I don't have the above mentioned tire issues as described, should I refrain from replacing them until they exhibit those signs?

Let me ask you this, is your life worth $1,000? Mine is and I don't have much going for me. If you don't want to spend a bunch, get some sumitumos on there.

[SBAquaLT5]

What is the date stamp?

Conventional practice is if I took a (never used) 5 year old set of tires to a good shop to install, the tire shop would not install them regardless of how they look due to liability. This is because even in the best environment, rubber degrades and looses it's performance characteristics; more of the compound turns from elastic to plastic, out-gasses, and what you can see on the outside is not always the same as what's happening on the inside. Aging, as mentioned is exacerbated by heat cycles and sun damage.

That being said, if you are not driving them more than back and forth to the market they *might* be OK for another year, but I would suggest looking for a replacement for piece of mind and safety. Tires are the #1 performance and handling component for a car and relatively cheap insurance.

[efnfast]

When I bought my car, it was 20 years old and still had the factory fronts. (Which I still have if anybody needs for NCRS). While on the highway, if I found a crack in the road, it would pull me right into the next lane. Scared the crap out of me. I new set of tires totally solved that problem.

[Bob Eyres]

Think of replacing your tires as insurance for your peace of mind. This is if you drive the car as intended.

In the garage,I still have the original tires that came on the car. But they’ve only been kept because I keep all original parts.
Because I exercise the car to 7K nearly every time I drive it, it would be foolish to put the original Gatorbacks on unless I was going to some judged event. Which I never do.
My formula is to calculate how many miles per year you put on the car, then multiply by 5, then buy tires that will wear out at that mileage.
Most ZR-1 owners put less than 5K miles per year, like I do, and don’t drive in the rain.
My last choice was Toyo R888’s, soft autocross gumballs that stick like glue, but still have some sipes that will not kill you if it rains. And they’re cheap.
Bottom line? Why wear tires that don’t allow this great car to do what it does? JMHO


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[lfalzarano]

Think of replacing your tires as insurance for your peace of mind. This is if you drive the car as intended.

In the garage,I still have the original tires that came on the car. But they’ve only been kept because I keep all original parts.
Because I exercise the car to 7K nearly every time I drive it, it would be foolish to put the original Gatorbacks on unless I was going to some judged event. Which I never do.
My formula is to calculate how many miles per year you put on the car, then multiply by 5, then buy tires that will wear out at that mileage.
Most ZR-1 owners put less than 5K miles per year, like I do, and don’t drive in the rain.
My last choice was Toyo R888’s, soft autocross gumballs that stick like glue, but still have some sipes that will not kill you if it rains. And they’re cheap.
Bottom line? Why wear tires that don’t allow this great car to do what it does? JMHO


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Thanks Bob. I only drive it less than 400 miles per year and maybe attend a charity lap event at VIR. The VIR event is the most concerning, because of the high speed cornering and top speeds of 150 mph on the straights. A tire failure could be very damaging to the car and me. At almost 70 years old, I’m not the same driver I was 50 Years Ago. Thanks again.


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[lfalzarano]

What is the date stamp?



Conventional practice is if I took a (never used) 5 year old set of tires to a good shop to install, the tire shop would not install them regardless of how they look due to liability. This is because even in the best environment, rubber degrades and looses it's performance characteristics; more of the compound turns from elastic to plastic, out-gasses, and what you can see on the outside is not always the same as what's happening on the inside. Aging, as mentioned is exacerbated by heat cycles and sun damage.



That being said, if you are not driving them more than back and forth to the market they *might* be OK for another year, but I would suggest looking for a replacement for piece of mind and safety. Tires are the #1 performance and handling component for a car and relatively cheap insurance.



Thanks for your advice. The date stamps are XX12’s (too cold in the garage to check the month ☃️). I agree with what you’re saying. You want optimal performance when you need it, otherwise I’d be calling Hagerty for my Insurance claim.

Lou


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[Bob Eyres]

Note that these Toyos are V rated, which are good to 149 mph. W and Y are the top end tires. Y are rated to 186mph which would theoretically be the most appropriate tires for the ZR-1.
At 73, my top-end days are over. An occasional squirt to the 150 is all I dare:). So it’s the Toyos for me.


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[ZR1CK]

I have a '91 with 25k ms and original tires! I don't drive the car had, except maybe once in a while, but did decide to purchase new tires just recently. The originals still have good tread on them so what I plan on doing is to purchase a set of 5-spoke Z wheels and save the original tires and wheels, for whatever. I replaced the original exhaust a few years ago and still have that hangin' around...for whatever. Anyway, I'm lookin' forward to this Spring and cruisin' with the new "shoes", aaannd feeling more secure in doing so.

:saluting:

[Riviera]

If you are even remotely thinking of putting that car on a track, I would absolutely replace the tires. Even if you are not driving at racing speeds there are a lot of tire stressors on a race track.

[lfalzarano]

Thanks everyone, you can’t take it with you, so get new tires... time to go shopping online while it’s cold outside ☃️❄️!


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[doctorjay61]

Thanks everyone, you can’t take it with you, so get new tires... time to go shopping online while it’s cold outside [emoji951]️[emoji300]️!


Sent from my iPhone using ZR-1 Net Registry (http://r.tapatalk.com/byo?rid=90383)My Nitto nt05 have a a date code of 0810 but they only have 7,000 miles on them. I guess the consensus would be to replace despite the mileage as they are approaching 8 years old? Never did any tracking as of yet, but noticed they break loose a bit during spirited shifts.

Dave

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[DRM500RUBYZR-1]

Yes,
Replace the tires.
Marty

[Paul Workman]

My Nitto nt05 have a a date code of 0810 but they only have 7,000 miles on them. I guess the consensus would be to replace despite the mileage as they are approaching 8 years old? Never did any tracking as of yet, but noticed they break loose a bit during spirited shifts.

Dave

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Yep, I feel your pain! But, it's my fault for not driving more, I recon.

In my experience with the GY D3s AND the Nitto 555/555r, at and certainly beyond 5 seasons they start acting like the temperature was near freezing. They often break loose w/o coming close to "standing on it" in first gear, and getting a little "sketchy" when going through some "S" curves or the occasional on-ramp.

Last season while driving the twisties during the Mountain Run, I felt the ABS kick in when going into a few turns. Course, it could have been a lot of things too. But, this "feeling" I've noticed now on 3 sets of tires at about the same number of seasons for the way I've driven on them. Time for new rubber!

I've had great luck with the Nitto 555/555r combo. At the last pizza night, Bob Gillig was saying that he found the Nitto NT01s would really stick well on his 427 LT5 ZR-1. (And, when Bob talks...people listen.)

Ami's ZR-1 has the Nitto G2s on the front which seem to cleave water better than the 555s, FWIW. (A new set w/ road hazard is just at/about $1K at Discount Tire, including road force balancing, and free balance and rotation.)

I seldom drag race - preferring the twisties for most of my driving. And, I really hate driving in the rain with the 555/555r combo - pretty "squirrely" above 45-50 mph in moderate to heavy rain, I find. However, I've followed Robert DeMarco's car which had the 555 G2s in both moderate to heavy rain, AND through the twisties. And, if you know Robert's driving style in the mountains, he ain't shy about laying into the corners! He spoke well of those tires, last we spoke.

Bottom line - it all depends on how the car is to be driven whether or not to change them on account of their age. If they aren't sticking as well as you'd expect, regardless of age, a different tire may be needed.;):cheers: