[JRTJH]

You didn't include any specific information on which Honda Pilot you have (2WD/AWD/towing package) so I can't give you any specific numbers, but the following is directly from the 2016 Owner's Manual:

"5,000 lbs. maximum towing capacity for AWD models with accessory ATF cooler; 3,500 lbs. for AWD models without accessory ATF cooler and 2WD models. Towing requires accessory towing equipment. Please see your dealer for details."

Additionally, if my research is correct, the Curb Weight ranges from 4023 to 4317 pounds, the Gross Vehicle Weight Rating (GVWR) is 5,545 to 5,842 lbs and the Gross Combined Weight Rating (GCWR) for the Pilot is 9579.

So, if we consider that you have an AWD with the appropriate towing package with transmission cooler, your vehicle should weigh around 4300 pounds. Add 4 adults at 150 pounds each (600 pounds) and you are approaching 5000 pounds in your vehicle. Add the 150 pounds for an equalizer hitch (minimum hitch required for a trailer weighing 4500 pounds) and you're around 5150 pounds. That leaves a maximum for the trailer tongue of 395 - 692 pounds. With a vehicle load of 5150 and a GCWR of 9579, the maximum trailer gross weight you can tow is approximately 4429.

The Passport 175BH has an empty tongue weight of 410 pounds. Add 40 pounds of propane and 45 pounds for a GP27 battery and your empty tongue weight before any cargo, food, clothing, camping gear, tools, personal equipment will be approximately 495 pounds. That is very likely more than the capacity you have remaining (395-692).

If we assume that you do have the Pilot AWD with the towing package AND the additional transmission cooler, you are "on the verge of being overloaded with an empty trailer". If you have a PilotAWD without ATF cooler or a 2WD version then the empty trailer will be significantly heavier than the maximum capacity of your vehicle which is a maximum of 3500 pounds.