Russ,
Yup, the issue is the cable valves have an 8 ft cable that is sealed at both ends. So no way to lubricate the cable, the valve ain't anywhere near 8 ft from the pull handle...so its wadded up under the belly and the cable is cheapo, doesn't have a synthetic liner inside the housing...
Along with the Valterra electric valves I recommend adding at Valterra twist on valve at the end of the drain piping where you hook on to drain. Makes danged sure you don't get a lap full of you know what. For $19.30 you can't go wrong. I have them on both drain connections an just leave them there all the time.
Here's a link:
https://www.amazon.com/Valterra-T58-...on+waste+valve
Pirate