If you can work it in and out by hand, try lubing it from the top (engine) end. It worked for me. I used gear oil with a moly additive. Loosen the clamp nuts so you can cant the end of the sleeve upwards and the oil can drain down into it.

I did this four or so days in a row. Each day it got a little better. Once it started retracting again, I worked in some silicone grease.

Now it's fine. Lots easier than changing the cable.

Good luck.

Doug Harvey