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The only reason that nut would have come off is if it wasn't installed properly in the first place. Either it was reused from the original strut (they should be replaced whenever removed) or it was not torqued properly. The torque specification for that nut is 42-56 ft. Lbs.
The disassembly/reassembly procedure is pretty straight forward. According to the attached diagram, simply disassemble in the order shown and reassemble in the reverse order.
Saturday, September 21st, 2019 AT 7:07 AM