I'd like some feed back on amsoil. I have 260,000 mi. on a '95 dually, 5 spd. A lot of my trips to the coffee shop are less than 5 mi. I'm currently using Exxon XD-3 Extra 15W-40. Anyone know about this oil? Of course I'd like the best like most people, so should I stay with this or switch to amsoil, or what?. Thanks for all the advice in advance. Everyone have a great holiday and let's remember, Who the season's about. God bless! Kirk