Yes, I am aware this thread is a bit old.

I highly recommend Amsoil. I have been using them for everything, and they have been great. I even put a bypass oil filter on the engine, 12k miles on the oil and it looks as clean as when it came out of the bottle. I'm sending out a sample soon to see how it's wearing. Here is a page for your truck, with all the recommended fluids: http://ww2.amsoil.com/mygarage/Vehic...0HD%20PICKUP+C

Every company says they are the best, and only show stats that show them in a good light, but I have yet to see anyone claim their product outperforms Amsoil, and if they lied, would be quickly sued for false advertising. If you want to know about oil, take a look at http://www.bobistheoilguy.com/ or google on cumminsforum.com and you will learn more than you ever knew existed about oil. ;-)