By 1980 Unser was replaced by Johnny Rutherford after having disagreements with Hall. The only change to 2K was its number, now four. Rutherford won five races that season, including the 1980 Indianapolis 500, the Datsun Twin 200 at Ontario Motor Speedway, the Red Roof Inn 150 at the Mid-Ohio Sports Car Course; the Norton 200 at Michigan International Speedway, and the Tony Bettenhausen 200 at the Wisconsin State Fair Park Speedway. He also won the 1980 IndyCar and CRL championships. In 1981 Rutherford returned with the No. 1 Pennzoil Chaparral 2K-Cosworth DFX and won the season-opening Kraco Car Stereos 150 at Phoenix International Raceway. The rest of the season proved to be inconsistent as he dropped to fifth in points. The team also competed in the opening round of the USAC Gold Crown season at the 1981 Indianapolis 500. Rutherford led for three laps early on but fuel pump issues ended the team's day after only 25 laps. By the 1982 IndyCar season the 2K was becoming outdated, with its best result in fourth place at the Miller High Life 150. After four races he ranked 18th in points. By the time of the Norton Michigan 500 at Michigan International Speedway, the team was using a March 82C-Cosworth DFX purchased from Bob Fletcher Racing. Rutherford's results managed to improve as he took his season-best finish of third at the AirCal 500K at Riverside International Raceway. Rutherford ended up in 12th place in points that year. The team also competed at the USAC Gold Crown season finale, the 1982 Indianapolis 500, where Rutherford started 12th and finished 8th.