I pull a 20 foot cargo trailer and once at a campground if it's not already level I do the auto level with the bags and trailer attached. Should I be disconnecting the trailer first? I don't want to hurt the system or new airbags
Armchair Expert answer:
I don't think you can "hurt" the system or your new air bags. Your air system can only put a limited max pressure (120 psi plus or minus) in the bags, whether you have the trailer hooked up or not.
What is the tongue weight on your receiver? 10% of trailer weight? The leveling system should be able to accommodate the extra weight on the rear end without any great difficulty.
Others may have differing O-pinions.
Guess my answer would be if you are going to disconnect the trailer anyway, do so first.
If not, leave it hitched and just level.
We see many motorhomes with big trailers in CG, often they are there for some time. They usually leave them connected, level the coach, put the tongue foot support down and most have trailer supports under the rear corners of the trailer if they are loading or unloading cars, motorcycles, UTV or anything else. This takes most of the load off the coach.
Been doing it for years. 22' trailer, probably 8K lbs total. Had a FT customer, that towed a loaded stacker, he did it.
Have another friend with a 28' tall trailer with Harleys and Jeep, he does it.
Chris