What size are the speakers in a 2003 Chevy truck?

The speaker sizes in a 2003 Chevy truck vary depending on the trim level and whether it's a Silverado or a Colorado/Canyon. There's no single answer. To know for sure, you'll need to:

* Check your owner's manual: This is the most reliable source.

* Look at the speakers themselves: Remove a speaker grille to see the size printed on the speaker itself.

* Consult a car audio parts website: Sites like Crutchfield allow you to select your year, make, and model to find compatible speakers, indicating the factory sizes.

Without this information, I can't give you a definitive answer.