Had 2000 Gen 1 Tundra 4.7
Had 2000 Gen 1 Tundra 4.7 dble cab. Transmission failed at 100k. Rear structural rusted out. Never got better than 20 mpg empty at greater than 65 mph. 10 mpg towing 23 ft RV.
Sold at 150k miles.
Got 2010 Gen 2 w/5.7. Never got above 18 mpg empty at 65 mph or more. Towed my 25 ft RV okay, but not efficiently. Never got better than 10 mpg... mostly 8 and 9 mpg.
Rear axle bearings failed just outside warranty.
O2 sensors and related intake system died just outside of warranty.
Overall a good truck. Sold at 190k miles.
Got a new 3 liter diesel Silverado in May. Getting 12 to 14 mpg towing 27 ft RV and 24 mpg towing boat. Best 50 miles empty is 33 mpg at 70 mph. Comfortable and plenty of torque to tow.
Toyota took too long to come out with next gen Tundra.
I may look at hybrid if it pans out as good tow vehicle.