I tried to loosen a tie rod on my 911 and it would not budge after hitting, banging and a wide assortment of four letter words. Soaked it in PB Blaster for five minutes and it came off with a crescent wrench. The other side didn't budge with LW or WD, and then came off after a PB soak. I'm converted.
They also make a spray lubricant that has Teflon in it. It leaves blue-grey residue behind after it dries, so you need to be careful where you use it, but I haven't found anything better for getting old stuck locks to work like new. I use it on the cheap locks on my pickup tool box, and the keys slide in like butter.
Case-IH Farmall 45A, Kubota M8540 Narrow, New Holland TN 65, Bobcat 331, Ford 1920, 1952 John Deere M, Allis Chalmers B, Bombardier Traxter XT, Massey Harris 81RC and a John Deere 3300 combine, Cub Cadet GT1554
Kroil is also a very good one but you have to order from Kano labs to get it. They have a lot of different products for almost any application. Kano Labs website