Castrol GTX it is Engineered to provide maximum protection against viscosity and thermal breakdown!
Baby oil is good to use, and also has other uses like rubbing it all over your girl...for that "wet" look.... :1orglaugh
I've use this before, and I actually prefer it to the baby oil for lubrication
http://www.stayswetlonger.com/wetproducts/wet_original.shtml
I don't like baby oil for hand jobs. Spit works well though.
coconut oil, great for massage too.