Tires: tire campatability, 2008 nissan titan, chevy silverado

Question
Are 2008 Nissan titan tires interchangable with 2003 silverado chevy trucks?

Answer
Terry,

No.  

First, there are a variety of Nissan Titans, and they have difference tire sizes.  Chevy Silverado's also come in a several varieties - and those have different tire sizes.

For example a 2008 Nissan Titan takes P275/60R20 or P275/70R18, while a 2003 Chevy Silverado takes P235/75R16, P245/75R16, P255/70R16, P265/76R16, P275/55R20, LT245/75R16, or LT215/85R16.  Notice there is no commonality.