Dont feel bad, my 04 sport has the Dunlop Grandtrek A/T. They are a pretty smooth tire, not too bad in rain, but they have or I hope its the tire, a roar at around 73 mph. I will tell you a little bit about my tire experinces.
I have had 2 Tundras. My 1st one i replaced the factory Dunlop with Michelin cross terrains. This is when they first came out. I didnt get 25 k miles on them. They were the worst tire I have ever had. Then I replaced them with LTX M/S. I have had 3 sets of these tires on various vehicles. The day I bought my wifes Rx300 AWD, I put LTX'S on it. I got 98k miles on those tires. The only reason I replaced them was because they were starting to dry rot on the treads. I was a little suprised by that. I dont know what tire I am going to be put on my Sport, I have 15k on it now. I have only had it for 4 monthes!!! I want some good traction.