The throttle body may need replaced due to a crack or flaw the the thrttloe mechanism. Is a dealer wanting to change it? Have you experienced problems with your Tundra?
If you are having it replaced there are various sensors and wire harnesses attached to the throttle body. You will also have a throttle cable since Toyota didn't go to an electronic cable on their 4.7 liter V-8 until the 2003 model year.