My RV's front tank has problems because of the very long distance from the filter neck to the tank if the nose is facing downhill due to the long horizontal pipe, which can happen sometimes if a station wasn't built very level. I never have rear tank problems, but the tank is very close to the filler neck so no long pipe like on the front.
Are you filling in truck lanes with big nozzles or in auto lanes with small ones? That can make a difference. Some stations are worse than others too, even with the smaller nozzle.