Have you changed the Fuel Filter? I was having the same problem and changng the fuel filter fixed loss of power, poor gas mileage, poor shifting ect.. The truch will act funny the first 20 or so miles after changing it because it has to reset for the adjustment of fuel flow..
The EPA mileage estimate for the 2001 Toyota Tundra is 15 mpg in the city, 18 mpg on the highway.
The EPA mileage estimate for the 2012 Toyota Tundra is 16 mpg in the city, 20 mpg on the highway.
The EPA mileage estimate for the 2008 Toyota Tundra is 15 mpg in the city, 19 mpg on the highway.
The EPA mileage estimate for the 2007 Toyota Tundra is 15 mpg in the city, 19 mpg on the highway.
The EPA mileage estimate for the 2006 Toyota Tundra is 14 mpg in the city, 19 mpg on the highway.
The EPA mileage estimate for the 2009 Toyota Tundra is 15 mpg in the city, 19 mpg on the highway.
The EPA mileage estimate for the 2013 Toyota Tundra is 16 mpg in the city, 20 mpg on the highway.
The EPA mileage estimate for the 2014 Toyota Tundra is 16 mpg in the city, 20 mpg on the highway.
The EPA mileage estimate for the 2004 Toyota Tundra is 15 mpg in the city, 18 mpg on the highway.
The EPA mileage estimate for the 2002 Toyota Tundra is 15 mpg in the city, 18 mpg on the highway.
The EPA mileage estimate for the 2005 Toyota Tundra is 14 mpg in the city, 19 mpg on the highway.
The EPA mileage estimate for the 2011 Toyota Tundra is 16 mpg in the city, 20 mpg on the highway.