Good question. Ravage and Grimlock definitely were. Beta is implied by Rav's profile. According to IDW ten years later: Ironhide, Silverbolt and Prowl. Most of the rest are rubbish retcons... in the godawful Wreckers comics Arcee, Springer, Devcon and Rodimus (with the lamest Maximal upgrade ever). Razorclaw, Divebomb, Laserbeak and Buzzsaw according to the Timelines comics.