From Wittenberg, the 35-year-old Mears traveled to the
University of Tennessee, becoming one of the NCAA's most successful coaches during his 15-year stint there. He compiled three Southeastern Conference championships between 1962 and 1977 sat out the 1977–78 season. Under the watch of interim coach Cliff Wettig, the Volunteers struggled to an 11–16 record, and Mears officially retired for health reasons after the season. He retired in 1977 after 21 years of college coaching and a 399–135 record with no losing seasons and a .747 winning percentage. After leaving coaching, he served for 10 years as athletic director at the
University of Tennessee at Martin (UT-Martin). One of the prime achievements of Mears' tenure at Tennessee was the introduction of the phrase "Big Orange Country" to the Volunteer fans. Before his arrival, Tennessee fans almost never wore orange away from the field or court. As an Ohio native, Mears recalled the Steubenville "Big Red" and liked the name and all it implied. The Volunteers, Knoxville, and the rest of the state took the concept to heart. Indeed, years later, longtime Vols radio voice
John Ward said that many of Tennessee's athletic traditions originated with Mears. For instance, the longstanding tradition of the football team running through a "Power T" formed by the
Pride of the Southland Band originated with Mears having the basketball team run through a giant "T" as they took the court. He was also responsible for "
Rocky Top" becoming Tennessee's de facto secondary fight song. Mears was also known for his innovative pregame shows. Mears would often, particularly for important away games, walk the perimeter of the floor in his Big Orange sportcoat, both engaging and enraging opposing teams' fans. He also demanded green jello for his pre-game meal. One time before an away game, Mears and the team were eating at a restaurant and the restaurant, as a joke, served Mears orange jello. The coach became quite angry and demanded the restaurant serve him his customary green jello. They did (at great trouble to their staff) and UT narrowly won the game. Afterward, Mears attributed the victory to the green jello. ==Head coaching record==