Setexan is right it is sure to stir the pot. Opinions very on whether Dyno or Synthetic oils are better. Personally I use synthetics throughout my truck to help ensure I am getting the most out of it.
A lot of guys will tell you change your oil every 5-7500 miles and don't worry about it. I don't believe in that. With dyno oil, it begins to break down very quickly after you start using it. When it breaks down, turn to sludge, varnish or vapor all of which don't help lubrication. Synthetics, being made from chemicals and not pulled from the ground hold their lubricating properties together better than dyno.
Now there are several good synthetics on the market. Personally I have been using AMSOIL for several years in my gasser and now my dmax plus everything else in my garage. AMSOIL offers a full line of high quality, extended drain products that will help with fuel economy for your truck. They also offer fuel additives and other products as well.
With the fuel additives, regardless of which ones folks say are the best, stay away from ones with alcohol in them. While they might clean things up, they are going to dry things out as well and with our injectors we don't need that. With the use of AMSOIL products in my truck, I have increased my fuel economy by 2-3 mpg depending on what I am doing with the truck at the time.
If you decide to go down the road of synthetics and would like some more information about
AMSOIL, don't hesitate to PM me.
Take care,