His death was announced by his son Wade, currently defensive coordinator of the Houston Texans.
"Bum is gone to heaven-loved," Wade Phillips said on his Twitter account. "He will be missed by all."
Oail Andrew "Bum" Phillips coached the Oilers for six seasons and later was head coach of the New Orleans Saints for four seasons and part of a fifth. He resigned as coach of the Saints with four games remaining in the 1985 campaign, handing the job over to his son for the rest of the season.
He compiled an 86-80 career record with most of his success coming with the Oilers.
With running back Earl Campbell serving as the Oilers' chief offensive weapon, Houston advanced under Phillips to the AFC Championship game at the end of the 1977 and 1978 seasons. The Oilers lost on both occasions to the Pittsburgh Steelers.
He was known as much for his folksy speech and mannerisms as he was for his coaching skills. Phillips wore cowboy garb on the sidelines and was never without his trademark 10-gallon hat.