@Racer88
There are a decent number of jack stands very similar to those in the shop here. I never use them now and they really should just be tossed.
The failure here was not like the ones you see online where the pawl has little contact, or a weld simply breaks on the upright. Those failures had a recall from what I can see.
No, the stands here actually folded like a cheap suit. And they folded on a car that was jacked up on all four corners just like yours. I kept them for awhile to show folks and warn them in person, but have tossed them. The chinese steel and the design was the major culprit as I have never had a stand fail except for those and I've had cars jacked up on all sorts of things from the garage to the race track on all types of surfaces and angles. since my teens Looking at your photos, the ones you have are not a lot different in design from the ones that failed here.
What made the stands fail here was that the car was jacked up on a slight angle. But, not much of an angle. Not enough to warrant failure and it is easy to jack a car up at a slight angle. Folks do it all the time when they jack up only one side the left or right side.
Here's what I began typing earlier when you started this thread. Yes, I know you don't have welder, so you can't do the fix for safety.
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Failure of small Harbor Freight stands happened outside my shop when a friend (an engineer, autocrosser, DIYer and highly technical guy) jacked up his car and placed it on four Harbor Freight stands. His Toyota ended up on the ground/concrete, but he was not under it. He had jacked the car up on a concrete entry area to my shop that had an ever so slight angle to get cars into the shop. How slight? We are talking about a 3-4 inch rise in about 15-20 feet (not much!). I watched the entire thing happen from my home 400 feet away. And, his car is arguably one of the lighter cars at around 2,000 pounds and he had it jacked up about as high as your car. The jacks failed on the end where the engine was in the back where most of the weight is.
I will never buy Harbor Freight "small" jack stands unless I weld a flat plate on the bottom that connects the four standing uprights that are fairly thin metal. I would use quarter inch steel plate, but I imagine 1/8 would work too. You need to connect the four legs basically and give them rigidity so they won't fold up on one side.
Race tracks and/or race sanctioning bodies can often require in their Supplemental Regulations that all jack stands have flat plates welded like I described. Mainly to prevent damage to their tarmac and paddock by jack stands digging into the asphalt. COTA, VIR and others require this. But, perhaps the most important reason is safety. Often you jack only one end of a car, or one half of a car at a track. And often it can be at a slight angle. Particularly in a paddock with tilted roads or areas that are not around the garages.
Just warning you man. I would not use those stands.