RV model number helps a lot. We don't know if it hydraulic or electric; schwintek, LCI, venture, etc. If it has one motor or two, etc., etc..
Since it's making a grinding noise it's probably the gearbox, but could be a pinion or rack gear. Hard to say without knowing a little more about it.
Salem 29RKSS Pushing a 2500 Mega-Cab CTD!
Gotta go campin!