Consumer Group Says Ford Ordered Less Weight on Tires

In its efforts to get better gas mileage for its Ford Explorer, Ford Motor Co. ordered Bridgestone/Firestone to reduce the weight of tires fitted on the popular sport-utility vehicle, making them weaker and more susceptible to failures, according to a report issued Thursday by consumer group Public Citizen.

The report seeks to bolster Public Citizen’s previous claims that the design of the light-truck tires, rather than quality control problems at Firestone’s plant in Decatur, Ill., is the cause of tread-separation failures linked to 148 deaths and 500 injuries in the U.S. alone.

Public Citizen said an analysis of consumer complaints received by the National Highway Traffic Safety Administration showed that non-recalled tires made at other Bridgestone/Firestone U.S. plants were just as likely to suffer tread separation.

The group again urged Bridgestone/Firestone, which has voluntarily recalled 6.5 million tires made in Decatur, to launch a wider recall that would include 5.6 million 15-inch Wilderness AT tires made at plants in Wilson, N.C.; Aiken, S.C; Oklahoma City; and Joliette, Canada.

“For the sake of highway travelers everywhere, all Firestone Wilderness tires that were made for Ford Explorers should be recalled from the market, not those just made in Decatur,” said Public Citizen President Joan Claybrook. “These tires on Ford Explorers cause catastrophic crashes resulting in horrible injuries and death.”

On Thursday, Bridgestone/Firestone officials insisted that the 15-inch Wilderness tires not covered by the recall are safe, saying Public Citizen based its analysis on “duplicate and potentially inaccurate reports” in NHTSA’s database.

“Public Citizen’s . . . latest report raises no new issues--it is simply a repackaging of the same unsubstantiated allegations they, and the plaintiffs’ attorneys who support them, have made since the recall began,” said Christine Karbowiak, the company’s vice president of public affairs.

Last month, Ford and Firestone told the NHTSA that the companies generally agree that small interior cracks--invisible from the outside--began the deadly chain of events. Firestone also reported that it had found some manufacturing problems in a rubber skim coat that led to less adhesion of the steel belts inside recalled tires made at the Decatur plant.

For the most part, the 32-page Public Citizen report--which prominent Arkansas plaintiffs’ attorney Tab Turner helped to write--is an account of how the Aug. 9 recall transpired and what both companies knew before the event. The report summarizes many of the legal arguments that Turner and other lawyers have been making in dozens of personal-injury suits against Ford and Firestone.

But the report also cites previously undisclosed documents and testimony by engineers from Ford and Firestone, suggesting that the auto maker compromised tire safety by reducing the weight on Explorer tires.

Internal Ford documents suggest that Ford was in a quandary over how to achieve the fuel economy of the Explorer’s competition while ensuring its stability.

One way was to incorporate “low-rolling-resistance” compounds in its tires, but that proved to be undesirable because the modified tires made the vehicle unstable, according to the report.

Public Citizen said a top Ford engineer recommended that inflation on tires be increased from 26 pounds per square inch to at least 30 psi. That request was never implemented because the change caused the tires of the Explorer to leave the ground in turning-test maneuvers.

In the end, Firestone lightened the tire’s rubber and steel components by 10%--from 30.1 pounds to 28.5 pounds--to improve rolling resistance and fuel economy.

“The tire was made lighter, less durable--and therefore . . . less robust--and more susceptible to tread separations,” the report stated.

Ford spokesman Ken Zino described as “laughable” the report’s assertions that the lighter tires were unsafe.

“The weight of the tire is largely irrelevant,” he said. “ The load-carrying capability of a tire is determined by [the] volume of air inside it.”

The Public Citizen report places most of the blame for tread separation and blowouts on a weak “wedge area” near the edge of the steel belts.

The wedge, a small strip of rubber inserted on and between both edges of the steel belts, strengthens the bond at the belt edge and reduces the risk of separation.

According to testimony by Firestone engineers, the tire maker had used a wedge designed for passenger tires on the Wilderness tires. Deposition testimony suggests that the company knew, at least through tire warranty claims, that the Explorer tires were coming apart too frequently.

In 1998, Firestone began using a wider and thicker wedge designed for light-truck tires, which are tougher, more durable and sometimes give a harsher ride.

Ford shares rose $1.81 to $26.94 on the New York Stock Exchange.