do you know what kind of steering you have?
I didn't until yesterday. If you have a Teleflex mechanical system, it seems to me you cannot really lube the shaft without taking it apart. It may not actually be the shaft that is grinding/squeeking, it may be the gears inside the helm.
I might be that your cable needs lubing, (specifically the 6 or so inches that extrude from the helm unit (under the dash) Again, if it is a Teleflex, you have a plastic slide (tube) on the non cable end of he helm. It shoudl screw off, and expose the cable. You my find that lubing that cable frees up the grinding shaft.
Depending on how old the system is, might be time to drop $180 and replace the helm unit/cable.
If it is not a teleflex (or teleflex style), ignore above.
chris