I have a 2017 Jayco Seismic Wave Toy Hauler with the original 2 Interstate AGM batteries which are now 4 1/2 years old. It seems that the batteries are not holding their charge as long when not plugged into shore power. I've had it off shore power for 1 day with the Battery Cutoff switch not on, meaning batteries are still connected. Volt Meter shows around 11 volts, but when you turn the Battery Cutoff switch on, the reading is 12.5 volt or approx 80%. If you activate the landing gear switch while the Battery Cutoff switch is on, the reading goes from the 12.5 down to around 10.7 volts. Seems to me that the batteries are just holding a surface charge when at rest, but when you put a load on them, they are shot. Does that seem right to y'all? Thanks