Stuck downtube adjuster

[Renard]

One of the downtube adjusters on my winter bike wont budge. The ferrule is ok though. I've sprayed some GT85 into it and hope it will free up. If it doesn't does anyone recommend loosol or anything else?

What about preventing a recurrence? Once it is free'd up just grease? Teflon? Lithium? Copper?

 

[Smokin Joe]

Downtube adjusters often sieze up, they get a lot of the crap that is thrown up from the front wheel even with guards on. Take the cable off and use a pliers to undo it then grease and refit.