There are no laws or regulations prohibiting the sale of tires manufactured more than six years ago, but both safety experts and many vehicle manufacturers recommend against using any tire older than six years. The results, they say, can be catastrophic.
Jack Crane of Danville can't forget that fateful day in 2002. His sons, Joey and Bobby, were driving through the Central Valley on Highway 5 when, without warning, the right rear tire blew, the Ford Bronco flipped and rolled into the medium strip.
"Bobby was still inside the car and without getting too graphic, Bobby was dying," said Jack Crane of Danville.
Nothing could be done to save Bobby. He died.
The teens put the spare tire on the Bronco the day of the accident. They didn't know that spare tire was 14 years old.
"It looked like it was in great condition. It had lots of tread. It had more tread than the other tires," said Crane.
The tread totally separated from the tire. The Crane's said at the time, the tire had only 2,000 miles on it. They sued Firestone and eventually settled.
"Even if a tire has been unused, has never been on the road, and is in perfect condition, it is degrading just sitting there," said Mike Danko, a product liability attorney based in San Mateo.
We found a warning in an owner's manual by Chrysler:
"Tires and spare tires should be replaced after six years, regardless of the remaining tread."
We found similar recommendations in an Audi manual and in another by Ford-Lincoln Mercury.
Video from a consulting company, Transportation Safety Technologies, hired by an attorney filing auto liability claims, demonstrates a tread tearing from a tire, something safety experts say tires six years or older are more prone to do.
7 On Your Side also obtained demonstration video from another consultant also hired by an attorney, Safety Engineering and Forensic Analysis. The video shows what can happen after the tread separates from a tire.
We got a first hand look at what can happen when the Alameda County Sheriff's Department put Michael Finney on a simulator. He was going 60 miles an hour when the front tire blew. He hit the brakes and narrowly missed the center divider.
"That's one of the main problems people have. They get on the brakes, and like we said, that causes a weight transfer," said Deputy Brian Frazer from the Alameda County Sheriff's Department.
Safety Research and Strategies has been documenting accidents blamed on old tires which have lead to law suits.
"We've identified more than 140 serious crashes that have resulted in fatalities or serious injuries," said Sean Kane of Safety Research and Strategies.
He says even tires sitting in a store's warehouse degrade over time, and despite that, still end up being sold on the retail market.
Investigative journalist Brian Ross of ABC News found retailers nationwide selling tires older than six years.
We wanted to see for ourselves, so we took our hidden cameras to tire retailers in San Francisco, the Peninsula, East Bay and South Bay.
The last few digits of a code on the tire represent the manufacturing date of the tire. The "459" on one tire means it was manufactured the 45th week of 1999. We found it at a Good Year store in San Mateo. Two other tires we saw at the same store were six years old.
Our investigation also found tires older than six years being sold at used tire shops. We found a 10-year-old tire at Tires and Brakes for Less in Oakland; a nine-year-old tire at Hillside Tires and Brakes in Daly City; and a seven-year-old tire at Rolling Stock Custom Wheels in San Francisco.
Rolling Stock called it a ploy to get people to buy more tires; Hillside told us this was the first they've heard that tire aging might be a problem; and Tires and Brakes for Less says they only sell tires in good shape.
All three stores declined an on-camera interview. Good Year also refused to answer our questions on camera, but a corporate spokesman told us:
"Proper storage, maintenance and inflation of tires, not the age of tires, are the primary factors in tire performance."
A spokesman for the Rubber Manufacturer's Association (RMA) agreed.
"Our association does not recommend a removal date for tire based on age because there's no scientific information to back it up," said Dan Zielinski of RMA.
That claim is true. However, the National Highway Traffic Safety Administration is studying the issue right now by artificially aging tires in a lab.
Selling old tires of any age is legal, but safety experts have pushed for requiring expiration dates on tires and for simplifying the codes on the tires. These are changes federal regulators and tire companies have so far resisted.
"Why would the tire companies object to that? I do not understand and I have a dead son. There's just no excuse for that," said Crane.
For more information you can check out Michael Finney's The Back Story. Click here
ABC News' Brian Ross reported on what his investigation found in other parts of the country. Read his investigation here.
Tire Aging Report from the NHTSA