Wheels falling off RX-7 redux

I guess there is nothing unreasonable to assume that the already vibrated-off nuts were rolling around on the rim for the 100 ft the car drove without falling off, and that each wheel's got down to its last one or two nuts all at the same time, so that they could all vibrate/shear off at the same time.

Of course. With a Miata that slow, the brain atrophies from never having to think quick.

Leon

Well, two things seem obvious: 1. since no other damage was noted, the wheels all came off because either the lug nuts came off or the bolts sheared, and 2. at least three of those wheels completely separated from the car at essentially the same time, so either the last lug nuts came off or the bolts sheared simultaneously.

If you've got a way around those points, please let us know.

-- Larry

Buncha wimps. The car only weighs about 2700 pounds, and there were lots of people there. They should have just carried it onto the jack stands. You could probably have handled one end by yourself... :-)

I have always been very careful with lug nuts, making sure that they are the correct size, tightened correctly, etc. It just seems really important that a wheel does not come off while driving. It hasn't happened yet.

If I am ever guilty of either not screwing down the lug nuts down far enough to engage correctly, or using the wrong size ones resulting in the wheels falling off, it will be the last time I ever work on any car.

Pat

Sorry to step in Leon, but I have one.

There is no "either" here. The lug nuts came off because they failed to properly engage the bolt threads, while the lug bolts remained intact with threads that could still be used afterwards with the proper lug nuts.

Leon saw this in person, he even personally inspected with the car. I am going with his assessment on this one.

Pat

Absolutely. A correct-size lug nut screwed on only partially can still hold a decent load but will eventually fall off. In that case there are "last" lug-nuts, the one or two remaining ones when the others have vibrated off, that may give plastically.

Here we have the situation that all of them popped off at the same time right from their original fully screwed-on state, by skimming over the tops of the stud threads, rather than shearing the threads significantly, let alone the studs.

Leon

We had a neighbor who had a wheel fall off on the Interstate in Holland; it has stuck in my memory. Since I am as forgetful as anybody, I make a habit of after changing wheels, to go once more around all corners to ensure they have been torqued down to spec.

It is not that I don't trust myself, just that I have so much evidence to the contrary.

Leon ;)

This brings to mind the lady who was selling five 280ZX's in various states of repair. I considered purchasing them to part out and decided against it.

Anyway, the one car that would start had lost a front wheel at speed after vibrating the lug nuts off, and she said that the lug nuts on every other wheel were loose with some missing. She came to the conclusion that a thief had loosened them all and then been scared off before removing the wheels. (yeah, huge demand there for a set of scuffed-up 1983 280ZX wheels)

About this time she also mentioned that the cars belonged to both her and her ex-husband, and that they were going to split the money as part of the divorce agreement. I asked if the car that the wheel fell off of was her daily driver before the accident, and she said yes.

I just shook my head sadly as I left. There is such a thing as being too cynical, and also such a thing as being completely naive.

I am pretty sure that I know who loosened her lug nuts.....

Pat

Pat,

.....I'm fixin' ..... is "Texan" and has no resemblance to English. Using "Texan" is ok, but not improper English. :-) (Go to bed Pat ! ) :-)

Bruce Bing '03 LS

PS: What the hell are you still doing in Texas ? I thought you were going Northwest.

Ummm, no you don't. Nothing you or Leon have said contradicts anything I've said. I have not asserted any reason why the lug nuts came off, just that they did.

-- Larry

I didn't see the car but is it possible that there were no lug nuts at all? A friend had a similar thing some years back but only one wheel was affected, he had a flat on his boat trailer, he and his son changed it in a big rush and when the wheel came off a few miles later each thought the other had put on the lug nuts! Somewhere on the highway is a hubcap full of lugnuts!

NOTE: If you knew the two people involved you wouldn't be at all surprised at the incident, they managed between the two of them to destroy an awful lot of machinery and the tendency to hurry no matter what eventually resulted in the death of the son.

Sorry, but Leon has already stated that the lug studs were barely damaged and would still accept the OEM wheels and lug nuts.

After this post, you listed sheared lug bolts as a possible cause that the lug nuts came off.

That is a contradiction since they were not sheared, unless of course, you are going to accuse Leon of lying, as you once did with me.

Pat

We have plenty of rain here, thank you, I don't need to travel for it. I also got smacked by that thing called circumstances. :-)

I'm fixin' to get there, which of course means anywhere from 10 minutes to 20 years.

Pat

No they were there all 20. That's how they managed to mess up the threads to some extent.

The only thing that I wonder about is whether he really got them torqued to spec. That would seem a lot of torque for them to come of so easily, not?

Leon

Leon, that's precisely why I asked if your region's tech inspectors had a torque wrench.

-- Larry