What do you mean by drive belt. If your talking about the serpentine belt, it should have an auto tensioner. Same goes for the timing belt. There is no adjustment. If the belt is loose then it needs to be replaced.
ed724
What is the drive cycle for a 2006 Toyota Sienna?
What is the drive cycle for a 2006 Toyota Sienna?
The 2005 Toyota Sienna has front wheel drive.
The 2008 Toyota Sienna has front wheel drive.
The 2002 Toyota Sienna has front wheel drive.
The 2001 Toyota Sienna has front wheel drive.
The 2009 Toyota Sienna has front wheel drive.
The 2007 Toyota Sienna has front wheel drive.
The 2003 Toyota Sienna has front wheel drive.
The 2011 Toyota Sienna has front wheel drive.
The 2014 Toyota Sienna has front wheel drive.
The 2010 Toyota Sienna has front wheel drive.