The Hall of Fame coach died of a blood disorder, his brother, Dick, said in a telephone interview from Dix Hills, N.Y.
McGuire was regarded as a transcendent communicator in his careers as coach and broadcaster.
"We lost a giant and a genius," said CBS announcer Dick Enberg, a longtime friend and colleague. "Al was the most unique and incredible person I ever met. He saw life at a different angle than the rest of us. He could cut through all of the fat and get to the bone of the matter quicker than anyone I've ever known."
Former North Carolina coach Dean Smith said McGuire never got the credit for his coaching acumen "because he didn't use the same Xs and Os as many other coaches did. Al was a maverick. He did it his way."
McGuire was one of college basketball's most successful coaches for 20 years, leading Marquette to 11 postseason appearances, capped with an NCAA title in 1977.
When the Warriors beat North Carolina to win the championship in Atlanta, McGuire did not join the celebration. He sat on the bench by himself, his face buried in his hands, crying. He retired shortly thereafter.
"On a campus with great scholars, I had great, great teachers here but none better than him," said Utah basketball coach Rick Majerus, a Marquette alumnus who served as McGuire's assistant in the 1970s and was head coach in the 1980s.
When McGuire retired last March after 23 years as a broadcaster, he said he had a form of anemia but was not more specific.
Majerus, who is taking a sabbatical in Milwaukee to care for his ill mother and recuperate from a heart operation, said he last saw McGuire on Wednesday night, when he brought him a big hamburger and a hot fudge sundae.
"That will be the last great memory," Majerus said. "He said he hadn't eaten meat in 12 days."
McGuire had removed the intravenous lines supplying drugs and blood transfusions and was facing death with dignity, Majerus said.
"He was just so happy to be free and he was not hindered by those things," Majerus said. "It was as if he was unfettered spiritually as well as physically."
McGuire played at St. John's before a brief NBA career that ended in the 1954-55 season. He then made his mark on the sport as a coach and broadcaster, earning him election to the Hall of Fame i 1992.
"He was fun to be with, not fun to play against," said former St. John's coach Lou Carnesecca, a schoolmate of McGuire's.
His head coaching career started at Belmont Abbey, a small school in North Carolina, in 1957, and he moved to Marquette in 1964. He stayed for 13 seasons.
He joined NBC in 1977, and his constant banter with fellow analyst Billy Packer became a staple for college basketball fans. "McGuireisms" such as "tap city," "white-knuckler" and "aircraft carrier" became part of the sport's vocabulary.
In McGuire's argot, a "thoroughbred" who was "dynamite" in practice and mediocre at "curtain time" was a "3 o'clocker."
"Al was never a professional broadcaster, so anything that he did on air was not contrived," Packer said. "He was able to articulate what he was seeing the way he thought he saw it. It was all natural, that's why it was so well accepted."
One of McGuire's famous lines came when Packer said North Carolina center Geoff Crompton, who weighed more than 300 pounds, had lost 15 pounds. Without hesitation McGuire responded: "That's like the Queen Mary losing a deck chair."
He moved to CBS for the 1992 NCAA tournament and worked for them until his retirement. He entered a suburban Milwaukee hospital in July and was later transferred to a managed care facility.
"Our family has marveled over the past months at his inner strength and enthusiasm to live each day to its fullest," McGuire's son, Al, said. "Even as his illness wreaked havoc on his body, he remained resolute in mind. He will be deeply missed."
McGuire had a career coaching record of 404-144, including a 295-80 mark at Marquette, for an overall winning percentage of .737.
The Warriors won the NIT in 1970, the last time a school turned down an NCAA bid.
That year, McGuire was unhappy with what regional bracket Marquette would be sent to by the NCAA tournament committee. So he took his team, which had a 22-3 record and was ranked eighth in the country, to play in the NIT. The Warriors beat LSU and Pete Maravich in the semifinals and then knocked off local favorite St. John's in the championship game.
Minutes after the title game, McGuire was asked if his decision made some people in Milwaukee unhappy.
"Frankly, I don't care," he said. "I felt we could win the NCAA, but I'm happy with any championship. I've never won one anywhere."
The Warrior lost in the 1974 NCAA title game to North Carolina State.
McGuire also was a master recruiter.
He mined the playgrounds of the inner cities, unafraid of bad neighborhoods like Brooklyn's Bedford-Stuyvesant. That was how he got his first major player at Marquette, George Thompson, who played from 1966-69.
"Everybody thought he was a basketball person. He wasn't a basketball person, he was a people person," Packer said. "The things I learned from Al had to do with insights into people."
Thompson, Marquette's career scoring leader, said he often treated his former coach to lunch so he could continue his education.
"Most of the stuff we talked about had absolutely nothing to do with basketball," Thompson said. "It was just life in general."
McGuire also brought in from New York such players as Dean "the Dream" Meminger and Butch Lee, the MVP of the 1977 championship and player of the year in 1978.
"My rule was I wouldn't recruit a kid if he had grass in front of his house," McGuire said in 1997. "That's not my world. My world was a cracked sidewalk."
Besides his sons Al and Rob, and his brother, McGuire is survived by his wife, Patricia; a daughter, Noreen, and six grandchildren. Funeral services were pending.