Roto, yes the power from the vehicles 13.8v alternator does indeed help. However, if you go to higher angles requiring more lift (1.2+) side to side that extra power from the truck runs out too. It does help though. What that tells us is that voltage is dropping at the jacks. I firmly believe the run of wire from the controller to the jacks is way way too small and requires a much higher gauge to maintain voltage and get the current back there. In theory, a group 27 is rated for massive amounts of amps per hour. Think about what a large vehicle starter pulls. I need to free up some time to do voltage tests along the current path. As I said before I'm convinced it's a power delivery issue and if not, I firmly believe you can't lift a 10 ton 45 foot Coach with a small electric motor. My 3914 has a very heavy load over the curb side axles, which is the kitchen slide, cabinets, etc. it all sits right back there, that rear curb jack is the weakest link, followed by the street side rear. When both front and back pull power to lift one entire side, that's when it also says game over. I'm not sure is Jayco has some back door deal with Lippert to be the only buyer of 6pt electrical leveling systems. I believe there are now 6 or 7 manufacturers of luxury crossover toy haulers, every other one of them uses LevelUp. "Reasonably level ground". That's their out.
Maybe we can all get a group deal on Bigfoot Hydraulic Leveling Systems. I'd be happy if Jayco gave me back my 3k+ for the system so I can put it toward the Bigfoot.
The other weak point is the Schwintek 12+ foot slide rooms. Again little motors where a hydraulic cylinder should operate. This was my first RV, and last for a while (can't afford to lose 20k on another new one already). Boy did I learn a whole lot, way too late. Truth be told I got my near loaded '14 3914 for 55k$. We were in the price ballpark for a Eagle, so I was never ready or prepared to shell out the 80k-95k$ for a 4000 2015+ unit or a 4200 Cyclone.