One cause of a noisy pump is a clogged intake screen. Our pump became very noisy shortly after our first outing, especially when the tank was below 1/3 full. After much vibration dampening effort, to no avail, I became aware of the intake "filter"(really a fine screen). I removed the filter, disassembled it, and found it clogged with plastic shavings from the installation process. Once cleaned the pump noise seemed to be much quieter. It's becoming noisy again, guess another filter cleaning is required.
2000 Winnebago Ultimate Freedom USQ40JD
, ISC 8.3 Cummins 350, Spartan MM Chassis. USA 1SG, retired;PPA,Good Sam Life member."We the people are the rightful masters of both the Congress and the Courts - not to overthrow the Constitution but to overthrow men who pervert theConstitution. "Abraham Lincoln"