Are you saying they will or will not work on an 04?
I originally meant the front pads but to be clear for future searchers the rear pads are the same as C5 as well?
Yes, ALL base C5 front pads will fit 04-06 front calipers. Rear pads/calipers are different than corvettes. ALL GTO rear calipers from 04-06 are exactly the same and use the same pads. Only difference is that the 05-06 calipers are red.
This is well documented on here as well with a simple search:
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