Sims played college football for the Oklahoma Sooners, where he was a two-time consensus All-American, and won the Heisman Trophy in 1978.

In the NFL Films highlight, rather than be tackled during a rushing attempt, Sims ran at, jumped, and, while fully airborne, kicked Oilers cornerback Steve Brown in the head.

He also set a total yardage school record that stood until 2004, when freshman Adrian Peterson ran for 1,925 yards.

After losing to the Arkansas Razorbacks 31–6 in 1978, Sims led the Sooners to two consecutive Orange Bowl titles in three straight appearances.

In his final game, he ran for 164 yards as Oklahoma beat the previously undefeated Florida State Seminoles by a score of 24–7.

In the 1983 NFC divisional playoff game at Candlestick Park against the San Francisco 49ers, Sims ran for 114 yards on 20 carries, but Joe Montana led the 49ers to a comeback victory, as Detroit kicker Eddie Murray missed a potential game-winning field goal in the waning moments.

The matter wound up in court, and on February 10, 1984, a federal judge voided the Houston pact, sending Sims back to Detroit.

[10] Sims' career ultimately ended midway through the 1984 season when he suffered a catastrophic right knee injury in a game against the Minnesota Vikings on October 21; in that game, Sims set the all-time Lions rushing record (now held by Barry Sanders) with 5,106 yards on 1,131 carries, or 4.5 yards per carry.

He offered to play the season with a blank check, allowing Lions management to assess his value and fill in the salary amount accordingly.

Sims hoped to meet with Lions general manager Russ Thomas and owner William Clay Ford Sr. to discuss a spot on the team's roster.

His numerous businesses included a nightclub, a radio station, a dry cleaner, and a car parts manufacturer.

[18] In 2007, a bronze statue of Sims was dedicated on the University of Oklahoma campus in Heisman Park, commemorating his 1978 award.

The local library displays a collection of his photos;[20][21] Sims said while at Oklahoma that he preferred his home town to big cities.