Our 5v has an clutch lock on electric motor drive for bedroom slide
And the two hydraulic slides stay closed due to hydraulic fluid on retract side of piston
If hydraulic solenoid leaked thru or leak on line/fittings then slide outs could move while in transit
If clutch lock failed in motor then bedroom slide could move while in transit
If ANY mechanism designed to 'lock' slide failed then they could move while in transit
Typically IF mfg. provides 'locking bars' to install on retracted slides it is because the MFG. knows w/o them the slides can move while in transit. And if they do MFG. can claim no responsibility due to owners lack of using them.