The tundra is a nice truck. My '05 Chevrolet 3/4 ton Durmax came from the factory wth 310 hp and 640 torque ( '06+ had 365 hp). All Duramax that have automatic trans came with the Allison transmission. Mine is a 5 speed, the 06+ is a Six speeed auto to help with fuel mileage.
I have raised the torque by 125 ft. lbs & the horsepower by 75 using a Bank's Engineering Ram Air Intake, a 4"diameter exhaust and the electronic programmer which has 6 different power settings. This is 5,000+lb truck that gets 18-21 mpg on the hwy. and will pull 14,000lbs. No it does not get 20mpg pulling 14,000lbs
All of the big three will continue to raise that bar again & again, but it may be a little while as they are all having trouble with the emission particle filters.
Diesil truck magazine did a full comparison of fuel mileage, overal comfort & towing a 10,000lb trailer up a 5% grade. Results were: Chevrolet -first, Dodge - second and the new redesigned Ford last. You hear reports of 8-10mpg on the new Ford.
Dodge was the standard for years and continues to be a great truck, it is due to redesigned in 1-2years.
If the tundra does make it to market, this will force Chevrolet to redo their's in the future also.
This is what makes trading vehicles fun, they just keep getting better.