Quote Originally Posted by 03GPScottyd View Post
What's the stock radiator hose diameter for a 2003 Grand Prix. Want to install my autometer temp guage but I need a hose adapter for it.

1 1/2

1 1/4

3/4

5/8

Sorry for the question but I'm at work and thought I'd order it while I'm here.
Either 1.25 or 1.5. Not sure off hand. But I am going to say at least 1.5".