Bridgestone to pay Ford $240 million in settlement

"Mike Hunter" > writes:

> Firestone tried to spread blame to Ford and Explorer owners, but the
> question of fault was settled by the litigation. The settlement went
> against Firestone.

Because, of course, a lawsuit always gets completely to the bottom
of all complex technical questions...

> Nothing about the Explorers design or the air pressure
> recommendations caused the tires to fail.. Ford proved that fact in court by
> showing the problem occurred only on Explorers and other vehicles fitted
> with Firestone tires from one plant, to the exclusion of all other tires.
> The problem did not occur on Explores fitted with other brand tires or
> Firestone tires for other Firestone plants.
>
> The unfortunate part of Firestone problem for Ford and the industry was it
> imbedded, in the publics mind, the erroneous perception that SUV have a
> higher tendency to rollover than other types of vehicles. That gave the
> anti SUV crowd an excuse to try and effect the sales of SUV they love to
> hate. That perception is unfounded in fact. The fact is NO automobile or
> light truck has a tendency to rollover, even those SUVs with a short
> wheelbase. The opposite is the truth.. Every car or truck, if lifted up on
> two wheels by whatever force has, by definition, has not only a tendency but
> indeed a propensity to fall back on all four wheels.

I'm afraid that your knowledge of vehicle dynamics falls a bit
short. On the contrary, any vehicle can be made to turn over, even on
level pavement, if only by some sort of abuse (e.g. bad inflation
pressures). The narrower the vehicle, and the higher its center of
gravity, the easier that is to do, other factors being equal. Some
design choices, e.g. the swing-axle rear suspensions of the VW Beetle
and early Corvair, can make the situation worse.

Ever hear of the Mercedes A-Class?

> The fallacy,
> perpetrated by the environuts, has lead to expensive engineering changes and
> increased government regulations over SUVs that does little or nothing but
> add to the cost of building those vehicles. The truth is fewer than 2% of
> ALL vehicles accidents, including cars and light trucks, result in a
> rollover.

But the truth is that rollovers count for a fairly large share of
fatalities. And that share is much higher for SUV's than for passenger
cars. I can't find the 1998 IIHS report right now; it's the latest
I've found that breaks down fatalities by model and accident type. But
it indicates that SUV deaths are far more likely to result from
rollovers than deaths in passenger cars.

> The fact is the vast majority of that 2% are the result of forces
> encountered during the accident other than instability. IE being struck or
> striking something, running up or down a grade etc.

Or sliding sideways into a curb.

> If raising the center
> of gravity of a vehicle two inches or less, as is the case with SUVs,
> actually caused a vehicle to rollover then one should expect to see six and
> eight wheeled trucks, that have a center of gravity of about six inches
> higher than the average SUV or light truck, rolling over on a daily basis.
>

And they do, even though they have the advantage of being driven by
trained professional drivers, and far less lateral acceleration
capability. Remember how Ford reduced the recommended inflation
pressure for the Explorer to reduce rollover risk? That was because it
reduced the maximum lateral acceleration. The maximum lateral
acceleration of a loaded semi is down around 0.5G, as I recall.

--
-Stephen H. Westin
Any information or opinions in this message are mine: they do not
represent the position of Cornell University or any of its sponsors.

Over the last 25 years I have driven on Michelins, GoodYears, BFG's and
Bridgestones. Only one brand ever separated on me... and it happened
twice with two different tires.

Guess which brand.

Never AGAIN!