Can A Truss Rod (or slot) go bad?

If the truss rod still moves the neck, the rod is probably OK. Could just be a rubbery (sorry for the technical jargon ) neck. Some are inherently less stable than others, from my experience.

If the truss rod keeps adjusting it back to playable condition, it's not really a problem-just aggravating.

Larry

 

Yup. +1

You can try to maintain a more stable humidity environment for the guitar, but beyond that all you can really do is keep adjusting as needed. Fortunately most all the movement is in the neck itself, so simply adjusting the truss rod should maintain the setup. Some necks just seem to be hypersensitive to humidity changes, and unfortunately there's not much you can do about it.

 

One thing to watch for, if you have an acorn-nut Gibson style trussrod it's easier to see, but be careful that you don't crush the wood under the nut or you don't get to the end of the threads. At that point, you'll notice the nut is much harder to turn (or it springs back). Then simply remove the nut and put a washer on there. You'll have to cut or grind the outside of the washers to fit, but you'll get a few threads and that means a few more turns of the nut which is more than enough.

As Larry said, some necks are rubbery (I prefer pasta analogies, fettucine if it's flexible, linguine or angel hair if it's really weak). Since removing the fingerboard and installing graphite rods is a drastic measure, you might be happy just tweaking the trussrod with seasonal changes. Count your blessings the trussrod nut isn't on the neck heel.