there is metal to metal contact in that mechanism
and I would expect that the slide moves around a bit within it's opening just a bit, as the coach rocks and rolls down the road...so no doubt there could be some squawking from it.
If the coach had been parked for while it could be that it just needs to be worked in a bit
or it could be that it is in badly need of some lube (even though now we know we're not supposed to do it)
or I suppose it could be that the gear/slide mechanism is dirty, dry, etc...
My suggestion...watch that video to learn a bit about how that mechanism works.
Maybe watch their others too just for future reference....
then go out and look things over, clean as needed, and check for damage etc...
and get some of that recommended PTFE lube and give it a spray as directed, as best as you can.
I'll bet that'll quiet it down a bit
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