Do the batteries need water?
Your Chinook doesn't have a generator?
All batteries loose significant capacity when cold, especially below 0F cold. If you don't have a temp compensated charger, those batteries are getting badly undercharged, even with good solar. At low temps they may need 16V for a full charge.
Do you have a battery meter? Failing to fully charge them every 3-7 days will kill them fast. A full charge after 5 days of partial cycling may take 20 hours at the absorb voltage (charge until the return current drops to 1% of the rated capacity).
Willy. On your push button cabinet latches. How are they working? I've read some reviews about them them not working good. Are they hard to install?
Quick little video showing how she goes in the snow! We got about 12” of snow overnight, had to help 3 other people out the lot that were blocking the exit. Then I pulled right out! That night at Copper Ski resort the parking lot was a **** show. Probably got another 8-10” during the day. Must have been 100+ cars and truck stuck in the lot everywhere! I helped a bunch of people and the rig was unstoppable thru the lot.