According to IFTN, Jack Reynor has been offered the role of the Texan race car driver (or biker) in Transformers 4. Reynor auditioned for the role three times.
"A source close to IFTN says Bay is keen for Paramount Pictures, which is
financing the film, to agree with his casting decision, and an announcement is
expected in the coming days."
This report comes a short time after the rumor of Nicola Peltz and Brenton Thwaites joining the cast. There is still no word on the casting for the lead actress role.