You hair gene comes from your moms side! If your moms dad had his hair you will not lose yours. I am proof of this as my dad was really bald by 30 and I have a FULL head of hair at 40!!!!
No, actually, I do think there is a strong possibility that the father can pass the trait. Just because autosomally, a gene can be located on the X chromosome, also means that the father has a large chance (since he has one X) of passing that gene along as well. I think there is only a rough 50% chance or the maternal grand-dad passing the gene down.