Spare tire

[Borrego Dave]

Gee Glenn, I like examples but DUI and a tire? If someone is DUI I really don't think the age of a tire is in their thoughts .
I can say that when I bought my SD and had it parked in the driveway, 30 days later the spare tire pretty much blew the tread off. Don't remember what the date code was now but it didn't look like it had ever been on the ground. I did replace all three before the first trip out. I do think with tires it depends on much they are used. Often use would tend, to my mind, to keep the rubber softer than sitting parked for six months at a time and getting a set to the rubber. No stats for that, just 50 years of my experience so don't beat me up to bad . YMMV

[floyd]

Originally Posted by Glenn Baglo

I never buy additional warranties either, but that's what the "How does it work" paragraph appears to be describing.

yup!

[floyd]

Originally Posted by Byron Kinnaman

I don't think that's true. Might have been 30 to 40 years ago, but today I doubt it. Would you like find some stats to prove your point?

No. but it is practically legendary that tire manufacturing defect rates have increased dramatically since the tire makers have gone off shore to contract with third parties.
Would you buy a tire with no warranty at all, believing that there is no chance of a defect?
It is generally undisputed of all products that failure rates are much higher at the start of service due to manufacturing defects than they are during the mid life of the product.
Anecdotally....
The only trailer tire I have replaced in the last 30 years due to a defect was 6 months old when it failed.
Recalls are apparently much more common than in the past as well.

[floyd]

Originally Posted by Glenn Baglo

Well, put it this way.
Thirty per cent of drivers involved in an accident are DUI.
Seventy per cent are not DUI.
Stands to reason that there is less chance of being in an accident if you are DUI.

Not?

That assumes that 30% of drivers in general are DUI.


Someone once determined that 75% all murderers in the U.S. had consumed potatoes within the 24 hours prior to their crime.

[gordon2]

What ever warranty a company offers is more about marketing than safety. I have a 50 year warranty on my standard asphalt roof. The roofing company does not expect the roof to last 50 years. Instead they expect something else to occur where they wont have to replace it, assuming they are even in business in 50 years. And if on the slight chance, they do have to repair it or replace it in 50 years, well then that is part of the cost built into selling the product.

So please be sure you don't mistake a tires warranty for an evaulation of its safe use.

[Glenn Baglo]

The warranty on your roof is for the shingles and doesn't cover the labor to install them. It's also pro-rated so you might get $1 from the shingle company at year 49.

[Dennis mn]

Originally Posted by Byron Kinnaman

I don't think that's true. Might have been 30 to 40 years ago, but today I doubt it. Would you like find some stats to prove your point?

Byron, I believe Floyd is correct, in my career as a maintenance engineer, I learned of the "bath tub curve". New stuff suffers from infant mortality issues. As time passes, reliability increases until some unknown point of time, at that point reliability begins to go away. I have had more equipment failures due to infant mortality than at the other end of the curve! This is why I make it a habit of buying two year old cars.

[gordon2]

Originally Posted by Glenn Baglo

The warranty on your roof is for the shingles and doesn't cover the labor to install them. It's also pro-rated so you might get $1 from the shingle company at year 49.

I only use that as an example of how a warranty does not correlate to safe use (or expected lifetime) of a product. I could provide other (better) examples but the point remains the same. The fact that a warranty does not reflect the life expectancy of tires is the focus here.

[Glenn Baglo]

And I was just trying to point out how much risk the company is undertaking with its "warranty". Most people don't read the fine print.

[Byron Kinnaman]

Originally Posted by Dennis mn

Byron, I believe Floyd is correct, in my career as a maintenance engineer, I learned of the "bath tub curve". New stuff suffers from infant mortality issues. As time passes, reliability increases until some unknown point of time, at that point reliability begins to go away. I have had more equipment failures due to infant mortality than at the other end of the curve! This is why I make it a habit of buying two year old cars.

The bath tub curve is a 40 year old concept. It hasn't been taught or written about in any technical journals or magazines that I know of for at 40 years. After the early rocket failures things changed. Quality standards changed a whole lot. Manufacturing practices have changed and a more consistent product is the result. More consistent product results in less early failures. More failed products are better analyzed than in the past which results in improved product. Heavy competition results in better product, manufacturers can't afford many failures for several reasons.
After 45 years in manufacturing I've witnessed and been part of the change. This concept applies across the board from Televisions to Alternators. In the 50s you could expect to get more 75,000 miles of use out an automobile, now we're upset if can't get 300,000 miles of use. Truck are expected to get 1,000,000 miles. Changes have happened.

[Byron Kinnaman]

Originally Posted by Glenn Baglo

And I was just trying to point out how much risk the company is undertaking with its "warranty". Most people don't read the fine print.

What is a warranty, it the manufacturer betting that his product will last at least the length of the warranty.

[gordon2]

Originally Posted by Byron Kinnaman

What is a warranty, it the manufacturer betting that his product will last at least the length of the warranty.

Only in part. Anyway if you think a warranty of X years means yours tires are safe for X years than go for it.. I am done

[Raz]

Warranty and insurance. Both arguments waiting to happen. Raz

[Dennis mn]

Originally Posted by Byron Kinnaman

The bath tub curve is a 40 year old concept. It hasn't been taught or written about in any technical journals or magazines that I know of for at 40 years. After the early rocket failures things changed. Quality standards changed a whole lot. Manufacturing practices have changed and a more consistent product is the result. More consistent product results in less early failures. More failed products are better analyzed than in the past which results in improved product. Heavy competition results in better product, manufacturers can't afford many failures for several reasons.
After 45 years in manufacturing I've witnessed and been part of the change. This concept applies across the board from Televisions to Alternators. In the 50s you could expect to get more 75,000 miles of use out an automobile, now we're upset if can't get 300,000 miles of use. Truck are expected to get 1,000,000 miles. Changes have happened.

May be an old concept, but with 40 years of Plant Engineering experience, I believe it is still valid. The cut off points have moved to to advances in technology; but new equipment still breaks, and it eventually wears out. The last new car I bought was a Jeep that was back to the dealer 50 times the first two years. The next two Jeeps were lease returns that were two years old and had no issues. I get tired of vehicles long before they reach the other end of the curve, so I can't speak from experience to that end.