Runaway tire sends car airborne - GIF

[Frank S]

So here is my update to watching this video.
I am amazed at the comments about "lug nuts failing", "wheel spacer failure" etc. Did not a single one of you who "claimed" the failure as such even take a moment and closely watch the video?? The lug nuts nor a spacer (if even applicable) were the failure. What we know is as fact, the spindle end failed. The cause can only be speculated at this point on this video. Based on the video provided the facts are as follows. Moments before the failure you can see the "wheel assembly" wobble. That was the point of spindle end failure and the caliper briefly held the wheel assembly in position. What is certain in this video is the truck is a 2 wheel drive. The "spindle" failed at the junction of the knuckle. Did wheel offset play a part? IMHO, yes it did. But the lug nuts nor wheel spacer failed. My best investigative opinion (watching this video) is a fractured spindle failure. Likely causes are, #1 previous fracture from accident impact, #2 Wheel center-line offset compounded with minimal side wall (tire) causing severe shock to spindle. I would at this point rule out wheel bearing failure since we can see the spindle is bright and not burnt and there is no "smoke" at the center of the wheel assembly (look at center of wheel assembly from 1 minute 3 seconds in slow motion and again at 1 minute 10 seconds) From the grainy video I would surmise a fractured spindle. Close up inspection of the knuckle and spindle end would reveal the actual point of origin of the fracture.

You are correct in that the rotor disk is still attached. However, in regard to a spindle fracture as being the probable cause of the wheel coming off, there is another possibility with a high probability. A few manufactures no longer actually use spindles on their light duty trucks they use a bolt on hub assembly Chevy and GMC for their HD 2500&3500 models use a 4 bolt hub assembly with 14MM bolts, their 1500 models have only 3 14mm bolts, the hubs are nearly identical for 2wd or 4wd the difference is some will not be splined for the CV assembly
Installing wide tires on spacer s and those near zero sidewall tires are as you said a huge factor in failures
Here is a picture of a hub I recently replaced on an HD2500 4WD

And here is a picture of a 1500 2wd

Edit I just did a search and this type of bolt on spindle hub seems pretty much industry wide