I was back in the midwest in June this year and was dying of the heat. My unit was not cooling the toy hauler down enough as well. I put the pillows in the two air ducts and it made a huge difference. We also kept the shades down in the daytime on the sun side, used the awning to shade one side and it really helped. I started to replace all my lights with LED lights to reduce the heat but after putting one set and running the lights I was surprised how much heat they put out. This was on the small light above one couch. Anyway, the biggest gain we found was the pillows in the air vents and cleaning the filter in the AC unit. Mine dropped ~18 degrees so we were happy.
