7:11 AM PT -- Law enforcement tells TMZ Sports ... Grosso passed away Tuesday at Hoag Hospital in Newport Beach, California. We're told there is no obvious cause of death at the moment. An autopsy is expected to be performed.
Skateboarding legend Jeff Grosso -- one of the biggest skate stars of the '80s -- has died. He was only 51.
Thrasher Magazine's Michael Burnett confirmed the news ... saying on Tuesday, "Today we have the terrible task of saying a heartbreaking goodbye to beloved verticalist, commentator and friend of the mag, Jeff Grosso."
The details surrounding Grosso's death are unclear. We're working on it. He is survived by his 8-year-old son Oliver, who Burnett mentions in his tribute to Jeff.
"Jeff went from number-one amateur to '80s superstar to cautionary tale and back again. His latest role as lovable curmudgeon, host of his own history-packed web series and keeper of skateboarding’s righteousness, unafraid to offend or annoy in his quest to educate, was by far his greatest – second only to being Oliver’s dad."
The "cautionary tale" is a reference to Jeff's struggles with substance abuse. He talked openly about issues with pain pills and heroin. In fact, Jeff OD'd 3 times before 2017.
"He will be sorely, sorely missed. Our hearts go out to his family and many friends. RIP," Burnett said.
Jeff shot to skate stardom in the '80s and went on to host "Vans' Love Letters to Skateboarding."
Jeff was also BELOVED by skate legends like Tony Hawk -- who paid tribute to Grosso.
"Jeff was a true skateboarder at his core, and a great wealth of entertainment, insight and valuable philosophy to a younger generation. I was lucky enough to skate with him over the last four decades and occasionally featured on his Vans’ Love Letters series.”
Hawk continued ... "One of the last times we spoke, we talked about how ridiculous it is that we still get to do this for a living and that anyone even cares what we do or think in terms of skateboarding at our age."
"I believe Jeff is a big reason that anyone truly cares, and skateboarding was lucky to have him as an ambassador and gatekeeper to its history. He was also a great father, which is obvious in his last social media post. Thank you Jeff, words cannot describe how much we will miss you."