You can try and get some lube down the shielding while it is the truck. Attack from both ends. Depending on how much time and patience you have remove the cable and tie in vertical position in garage and lube and free up the cable. Reinstall.
Yes you can free it up. Likely gritted up with dust and dirt.


~ HB
1966 Chevrolet K-10 | Ghost: formerly Flappy Fenders | In the Stovebolt Gallery
1962 Chevrolet C10
1962 Suburban