Coating on all black Hydraulic lines flaking off

[jts140]

Has anyone had this happen to them? All my Black hydraulic lines going to either the slides or 6 point level system the coating of plastic is falling off. My orange lines, which are the extend ones are looking good. But the black which are the retract lines are falling apart and showing the white fibers. Its a 2014 Montana. Thanks

[enblethen]

The outer jacket has come apart on many of my lines. It became brittle. Replacement lines from local hydraulic shop is made of different material and have no sign of coming off, at least none showing yet.