Trans fluid spec on 2003 Chevrolet Silverado SS

What is the OEM spec for auto trans fluid in the '03 Silverado SS, 6.0liter engine? Is it synthetic? Is it Dexron IV?

by in Glen Mills, PA on March 04, 2010
1 answer
ANSWER by , March 04, 2010
Napa shows Dexron III and Dexron VI and my other catalog shows the same two choices