I noticed that the threaded rod from the factory did not match up with the clevis. The clevises might thread up to one rod but not another. If you were flying around fine for a while and later noticed a problem, the threads may have seemed initially engaged but then failed when loads were applied that exceeded the pullout strength of the clevis. I just replaced all the pushrods with 4-40 rod and good quality clevises.

This problem is separate from the balooning issue on landing. I am going to add some weight to the nose to move the CG forward and see if that helps.