I would use bleach instead of peroxide 1/4 cup per 15 gallons of water in the fresh tank, use water pump to move the mix thru all the lines.
Let the mix sit over night in the tank and lines then run the mix out of the tank and flush until you can not smell the bleach.
2016 F350 6.7L LB CC Reese 28K 2014 Chaparral Lite 266sab
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