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This is the craziest thing I've ever experienced Two months...

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Dear Tom and Ray:



This is the craziest thing I've ever experienced. Two months ago, I had the rear tires replaced on my '92 Ford Explorer. Two days ago, the vehicle was wandering all
over the road. I thought I had serious alignment problems, so I looked at each of the tires. The left-rear tire's lug nuts were all loose, and one stud bolt was rolling
around inside the hubcap!

I took it back to the garage, and it replaced the broken stud. My first thought was that the mechanic didn't tighten the lug nuts enough when he changed the tire. But the
garage said if the lug nuts were loose, it never would have gone for two months of daily driving. The garage told me its wrecker driver has customers sign a waiver
every time he changes an aluminum rim on an Explorer, because they have a reputation for coming off.

Now the shocker: The garage man said, "Do you remember that wreck on U.S. 127 a month ago? Well, an Explorer rolled over because one of its wheels came off." Is
this fact or fiction? -- Andy

RAY: Sounds like fiction to me, Andy. I mean, if you forgot to tighten someone's lug nuts, would you admit it?

TOM: We've never heard of any particular problem with Ford Explorer alloy wheels coming off. And when we checked the National Highway Traffic Safety
Administration's list of safety complaints for the '92 Explorer, there were only three out of many hundreds that had to do with wheels coming off. That doesn't suggest
an epidemic, since those could have been due to mechanical screw ups as well.

RAY: There is a Technical Service Bulletin concerning the use of power air wrenches on Ford wheels. But that has more to do with the dangers of overtightening than
undertightening -- you can warp the brake rotors if you use an air wrench without a device called a "torque stick" that prevents overtightening.

TOM: And it might be that, due to this warning, some mechanics are being so careful NOT to overtighten the lug nuts on Explorers -- because customers come back and
scream at them for warping the discs -- that they're being too careful and leaving them too loose.

RAY: I tell the guys in my garage not to worry about overtightening the lug nuts. The way I figure it, if something goes wrong, I'd rather give the guy a new rotor than
explain to his widow that I was just being careful not to overtighten anything.

TOM: And it CAN take two months for loose lug nuts to come off. We've seen it happen before. At some point, one nut gets loose enough and comes off, and then things
go downhill rapidly. And in many cases, a wheel bolt or two will break, just like yours did.

RAY: There's no way to prove it now, but my guess is that one of two things happened. Either the shop turned down the air pressure on its power tools in order to avoid
warping the disc rotors, and simply turned down the pressure too much ...

TOM: Or, after tightening the nuts on one side, and maybe part of the second side, the mechanic got a phone call from his wife. Then he went to get some coffee, went to
the bathroom, stopped to chat with the secretary, and when he came back to your car, he forgot all about the nuts he hadn't tightened yet.

RAY: But at least you noticed the strange handling and had the good sense to pull over. That's a good lesson for everyone else reading today. If you had kept driving, the
wheel almost certainly would have fallen off. And then we might be explaining all this to your heirs instead of you, Andy.
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