Why do people think they need Timbrins/air bags or anything when the truck is loaded and sits level as the pic of the op's shows?
Trucks are supposed to "squat". Op drive your combo I bet everything will be fine!
It's ridiculous to see so many TV's with the ass end sitting high going down the road with the RV nose high because someone thinks they need to be sitting ass end high like when they are running solo. Also it makes for a very rough ride!
If you are within specs you don't need to add anything.