Drove on interstate around 250 miles. Refilled with 1/4 tank. Drove another 40 and started losing power. We are dead in the water. Truck will idle a little rough, but not bad. Blows blue white smoke when I push the accelerator. No power when I put in gear. Sometimes cuts off. Any suggestions. Oh yea, it's a 6.0 that has been bullet proofed. Engine and tranny temp are normal. Oil pressure is good.