It is for max
weight for the given pressure. Personally, I wouldn't play it that close. Also, depending on your speed limit, you need to adjust if you're over 65 mph, also. Unless it beats the camper to death, mine will be ran at max pressure. Experience has taught me they last much better that way. All my other trailers stay maxed all the time. I also don't have to worry about changing loads (not as big a deal on a camper).