Drain the grey water tank completely. Use a certified grey water dumping station found at campgrounds or some highway rest areas. Park the RV is your driveway, turn it off and disconnect any water connections to the RV. Put on the gloves and safety goggles. Use a mask if you are bothered by the odors from the tank.
Go to the RV's rear left side--the typical area for the grey water tank housing panel. Open the panel and locate the grey water tank. Unscrew the hose clamp at the nozzle of the grey water tank. Be prepared for residual liquid to spill out of the hose as you loosen the clamp and pull the hose out from the nozzle. Use the wrench to get purchase on the hose as you pull it off the tank. Discard the old hose clamp.
Remove the old grey water tank and set it aside. Push the new grey water tank into the housing. Slide a hose clamp onto the hose and then push the hose onto the new tank's nozzle. Slide the hose clamp over the hose area where it connects with the nozzle and tighten the clamp with the screw driver.
Seal the hose connection with the silicone caulk. Let the caulk dry. Go into the RV and pour a quarter of a cup of bleach into each drain or sink. This gives the new tanks a small amount of bleach to fight bacteria build up and odor.
Connect the water to the RV and turn on the kitchen and bathroom sinks to test the flow into the new tank. This will also dilute the bleach.
