SACRIFICIAL ANODE, other than the hot water heater ?

[Anders Laurits]

Most RVer's know about making periodical checks of the Hot Water heater's sacrificial anode. Yet, I have talked with some that have additional anode's that they have little familiarity with. Here is the link to the story with photo's and locations.
Blog | Oliver Travel Trailer

[Casita Greg]

Only needed if you have a trailer with an aluminum frame. They are used to prevent galvanic corrosion of the aluminum, which is a "noble metal" and will tend to corrode away before many other dissimilar metals. With a steel frame, it isn't necessary, unless you have a boat trailer which gets dipped into salt water a lot.