What model of truck is Mack in Pixar's Cars?

Mack in Pixar's Cars is a 1985 Mack Super-Liner.

Mack is Lightning McQueen's loyal transporter and serves as the main link between the racer and his racing team. His design is based on the Mack Super-Liner, a heavy-duty North American highway tractor introduced by Mack Trucks in the 1970s. The film gives Mack a red cab, matching Lightning's racing identity.

At the beginning of Cars, Mack drives Lightning toward the Piston Cup tiebreaker in California. After becoming exhausted, Mack falls asleep and loses track of Lightning, setting up the chain of events that sends the race car into Radiator Springs. Mack later remains an important member of Lightning's support crew.

Mack is often described generally as a semi-truck or transport truck, which is correct but less specific. The model-level answer is the 1985 Mack Super-Liner, not a Peterbilt or Kenworth tractor.