Gun Stock Oil Guitar Neck. Tru oil is a brand name for gunstock oil, and is a polymerized finish that will harden and seal the wood. Then i give it two coats of casey's gun stock wax.
It leaves a heavy, glassy finish, should be put on thin or it tends to bead and run. The oil may not be needed but it makes the grain pop like crazy. Before putting a drop of finish on and polished again with museum grade wax after the final coat of hand rubbed gun stock oil.
If the neck is very dirty, try murphy's oil soap diluted 3:1.
Tung oil and true oil aren't the same thing, but they do give the same sort of finish. Most often associated with gunstock oil, this is an excellent choice for a guitar finish, especially on necks. Conditioning, darkening, protecting the wood.). I personally prefer a tru oil finish due to the ease of application, and little to no maintenance later.