In my picture, with my car weighing 2,500 lbs., and the sling angles at 60 degrees, the horizontal force pulling sideways on each quick jack is 722 lbs. when the car is dangling from a crane. I think the threaded rods would handle that value even at their crappy low strength rating. Now, if we use the 750 lb. value to pull the car up the incline, the horizontal force on each quick jack is only 217 lbs.
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