Thanks for posting those links. The first one from the BMW forum was pretty much worthless as he gave no details but the second one was very interesting. I do agree that this is a very important subject and I do not take it lightly. Trust me, there is no one on this forum or any place else more nervous or paranoid about crawling under a car held up with jack stand then I am. Hell I never even felt 100% safe under a vehicle on a lift. That said, my analytical side won’t let me just jump to baseless conclusions or knee jerk reactions either.
So the guy in the second thread who had his truck fall on him admitted to using the jack incorrectly. The manual states “Use as matched pair to support one end of a vehicle only.”. This guy decided to ignore those instructions and even admitted that this wasn’t the first time. He had done this at least 3 other times before this failure occurred.
Now think about that for a minute… If someone came on this forum and declared any other tool by any other brand was a POS because he used the tool incorrectly 3 times and on the 4 instance of misuse the tool failed, he would be laughed off the forum. But in this case that’s exactly what this guy did and instead of laughter or ridicule, everybody’s reaction is to agree with him that the jack stand he used was a POS? How does that make sense?
Did the fact that he was only using one stand have anything to do with it failure? I think so. Why do manufacturers insist that the stands be used as a pair and not individually? At first I was thought it might have something to do with the weight ratings? Kind of like how 2 sticks tied together are more than twice as strong as each stick individually? Well that might be part of it but the more I think about it, I think the real reason has to do with the direction of the applied force.
If you lift the front or rear of a vehicle and place jacks stands on each side, the force applied to those stands from the vehicle’s weight is applied almost directly down. However if you only lift and support one corner, the force is now applied to the stand on an angle and jack stands are designed to have forced applied to them on an angle. I think that's ultimately what caused this failure?
I feel bad that this happened to this guy and it’s one of my biggest fears but I can’t help but think this accident was this guys own fault and not some design flaw or issue with the quality of the metal used. Would a better quality stand withstand this misuse better? Maybe but I’d prefer not to find out. I say use the jack stands as they were designed regardless of where they were made, how much they cost or what they are rated for.
Anyway, as a side note. If money is no object and you want some seriously beefy jack stands, check out these suckers that were linked to in that other thread…
http://www.mile-x.com/norco-81205-jack-stands.aspx