What does ST8 mean?

[SteveBBB]

I'm looking at GM card rebates and it shows $3500 back on double cabs with ST8 and $2250 back on double cabs without ST8.

[ember1205]

It's known as the "Silverado Custom" package. LS Convenience Package, Chrome Door Handles, Chrome Mirror Caps, 20" wheels, V6 motor, and only on the LS trim level.

[SteveBBB]

Thanks!!

[ember1205]

Took some digging with my absolute best Google-fu, but I found it! lol