I have a 2007 sonata and it has 6.5 in speakers front and rear. The tweeter appears to be 3/4". You can install 5.25 speakers with the proper adapter ring.
The 2004 Hyundai Sonata has a 2.4 L base engine size.
The 2002 Hyundai Sonata has a 2.4 L base engine size.
The 2010 Hyundai Sonata has a 2.4 L base engine size.
The 2006 Hyundai Sonata has a 2.4 L base engine size.
The 2005 Hyundai Sonata has a 2.4 L base engine size.
The 2007 Hyundai Sonata has a 2.4 L base engine size.
The 2003 Hyundai Sonata has a 2.4 L base engine size.
The 2008 Hyundai Sonata has a 2.4 L base engine size.
The 2011 Hyundai Sonata has a 2.4 L base engine size.
The 2012 Hyundai Sonata has a 2.4 L base engine size.
The 2009 Hyundai Sonata has a 2.4 L base engine size.
The 2013 Hyundai Sonata has a 2.4 L base engine size.