New Mexico football coach Mike Sheppard, whose program has produced just six victories in 31/2 seasons, was awarded a new 3-year contract by the university on Friday.

Sheppard, who is completing the fourth season of a 5-year pact he signed prior to the 1987 season, will continue to receive a base salary of $70,000 a year under the new contract, which will run through the 1993 season.However, the new agreement, reached in negotiations this week between Sheppard and athletic director Gary Ness, also provides a $15,000 a year incentive clause. Sheppard would earn that amount based on a five-step standard that includes academic achievement and progress toward graduation by the players and the social conduct of Sheppard's staff and players, among others.