I could hit 40psi on a certain stretch of road with my truck stone stock, without even having it fully laid out.
Towing across Canada with a 4500lb car on a 2000lb trailer, plus about another 2500lbs of shit (Ask Jim - he saw it LOL) I was 38-41psi all the time up hills.
Check it for codes if there isn't an over boost code, I wouldn't lose a whole lot of sleep over it, in my opinion.