Well, after swampratt's post in another thread, my opinion may be different now.Nothing beats Kroil for a penetrating oil. Typically sold in industrial supply houses, but I've seen it at auto parts stores.
After over 30 years in industrial maintenance work, nothing works better. Everybody swears by it.
http://www.kanolabs.com/google/?gcl...dWby2H7Lq1U3aCMY2YkidDfOT7zYl50YaArppEALw_wcB