4:00 PM PT -- LeBron James is mourning the loss of a fellow Cavaliers legend ... sharing his condolences in a tweet Wednesday afternoon.
"Rest In Paradise my friend!! You’ll be extremely missed here!"
Tait was the Cavs radio guy for each of LeBron's first 7 seasons in the NBA.
Broadcasting legend Joe Tait -- voice of the Cleveland Cavaliers for 39 seasons -- has died after battles with kidney failure and liver cancer. He was 83 years old.
Tait joined the Cavs radio team for the inaugural season in 1970 ... and stayed on the mic nearly every year until his retirement in 2011.
Tait was known for his signature calls over the years -- including the Miracle in Richfield in 1976, when the Cavs won their first playoff series.
He was also known for his classic opener and sign-off -- "It's basketball time at ..." and "This is Joe Tait. Have a good night, everybody!"
Tait was recognized by the Naismith Basketball Hall of Fame in 2010, when he received the Curt Gowdy Media Award ... which is given to outstanding writers and broadcasters.
Cleveland also honored Tait with a commemorative banner at Rocket Mortgage FieldHouse prior to his departure from the team ... which hangs in the rafters alongside the retired jerseys.
The Cavs released a statement Wednesday afternoon ... saying, "The Cleveland Cavaliers mourn the passing of one of our beloved founding fathers and the original, long-time voice of the franchise – Joe Tait."
"A friend and mentor to many over the years, Joe Tait wasn’t just a member of the Cavaliers family; he was a part of the Cavs story like no one else and his voice and unique, candid perspective reverberates throughout the team’s history. He will be dearly missed."
Tait spoke about his life in an interview published just days ago ... saying, "I’m not afraid to die," he told The Plain Dealer.
"I do wonder what happens after you die. If anything does. I’m curious to find out. I do know I’ve had a good life. Lots of people have been great to me."