2012 Silverado 2500HD Diesel

[Jake]

Yeah, I never unplugged my trailer with the Denali and never had issues (one thing that went right with that POS!). My Ford doesn't cut power entirely either, as the trailer lights will come on with the cab lights if you open a door with the truck off.

I noticed that the UHaul trailer had incandescent bulbs, not LED. I'm wondering if there was some wiring fuckery going on with that particular trailer and the bulb(s) affected caused a lot of draw as the truck sat for two days. Hopefully your batteries are still good - given the truck is only a 2012, I'd think they still are.

Slight correction about the trailer brake, too - it's not really an "emergency" brake, it's just not electric. UHaul trailers have a spring that, when you brake, compresses and activates hydraulic brakes on the trailer wheels. Just so you don't think #MightyMightyDuramax was stopping the entire load unassisted - it's definitely working harder than it would with electric trailer brakes, but it's got some help.

Assuming the UHaul trailer has working brakes in the first place. Which... is anyone's guess.