stuck front diff lock

[philmcC]

What is best penetrating oil to use to free off the pin. Not in any hurry so can afford to make many applications to free it up. Thanks pMcC

[Stesaw]

Plusgas seems pretty good.. or ATF.

[Aidan]

Plusgas or Wurth's Rost-off which I think is better, I get the neat liquid rather than the aerosol, but the first time I used the aerosol I was amazed as I watched the rust wash out of the blind hole the rocker cover spring clip sits in which was full of rust , the spring wouldn't easily move even with prybar under it and I didn't want to force the spring and shear the spring (which I have seen happen) leaving the remnant stuck in the head - a couple or 5 applications and it was free swivelling. Once removed and inspected there was about 1/3 of the steel gone for good, so replaced it, the new genuine one is still on the engine now and the cover (also genuine, as was gasket) has never leaked