Tundra 2000-2004 V6 Belt
2000-2009 4.7 V8 Belt
2005-2014 V6 Chain
2007-2014 5.7 V8 Chain
2010-2014 4.6 V8 Chain

http://toyota.custhelp.com/app/answers/detail/a_id/7690/~/does-my-vehicle-have-a-timing-belt-or-timing-chain%3F