Hot water heater rod

Just in case readers don't know what is an anode rod, please know is is a sacrificial piece of metal that is intended to rust and corrode away instead of the metal of your hot water heater.  In combination, certain metals form a galvanic cell, like a battery.  The less "noble" metal corrodes away (see https://en.wikipedia.org/wiki/Noble_metal).  

Originally posted by GLBCamper I had a hard time getting a good seal this year because the female threads in the heater were quite rusted. I buffed it and the threads on the anode with a mild brush on my dremmel but it still took quite a bit of pipe dope to get a good seal. I left it stored for the winter with the anode out. Is there something I should be doing to prevent the connection on the WH side from rusting? Can that be replaced without replacing the entire heater? DIY?

Nope, it's permanent. While anything can be done with enough $$$.. it wouldn't be worth it to try to repair. That said, I have never heard of one needing it. Yes the threads rust a bit. I just hit them with a toothbrush, fresh two layer wrap of teflon tape, insert, tighten until firmly snug. Our Airstream's WH is 35 years old.. works the same way..

I always stored with the anode in, one less thing to do in the spring, and keeps the threads protected. New TT doesn't have an anode.. so..

Probably lasts different lengths of time depending on your water source.  Ours has never seen or tasted municipal/city water.  Only well water, 99% of the time ours.  Still on our original anode rod, on our 2011 r-pod.

It's your anode rod. You should pull an inspect with each winterization. Clean the threads, flush your hot water tank and reinsert if it's OK.