He moved on to the same position with the Arizona Cardinals in 2013 before joining Steelers head coach Mike Tomlin's staff past year.
The Steelers didn't disclose a cause of death. Darryl had such an impact on the players he coached and everyone he worked with throughout his entire career.
Tomlin described Drake was "an awesome husband, father and grandfather".
Drake is survived by his wife, Sheila; three daughters Shanice, Felisha and Marian, and two grandchildren.
Canadian Andreescu stuns Pliskova to reach Toronto semis She'll play the victor of the second semifinal between American Serena Williams and Marie Bouzkova of the Czech Republic. Bouzkova beat Simona Halep of Romania 6-4 in the first set before the fourth-seeded Romanian retired because of injury.
Drake spent 21 seasons coaching in college prior to entering the National Football League coaching ranks.
Drake was in his second year with the Steelers and also served as the wide receivers coach with the Bears and Cardinals before heading to Pittsburgh. He played college football at Western Kentucky and later coached there.
He went into coaching as a graduate assistant at Western Kentucky in 1983, the beginning of a career that included stops at Georgia, where he recruited and coached Steelers Hall of Fame wide receiver Hines Ward; Baylor and Texas. "Any time you coach for 40 years, you impact a lot of lives", Cardinals coach Kliff Kingsbury said Sunday at Cards training camp in Glendale. "Let faith guide us all through this incredibly hard moment... sending prayers to all of the extended Drake family, especially to his incredible wife Sheila and their handsome children".
Cleveland Browns head coach Freddie Kitchens, who coached alongside Drake in Arizona, called Drake "a really good coach and an even better friend". The Steelers canceled their training camp practice on Sunday, and it's uncertain whether they will practice Monday.
Steelers wide receiver JuJu Smith-Schuster tweeted Sunday that Drake was "my favorite coach that I've ever had in this game". Practice is expected to resume Tuesday.