12:09 PM PT -- A rep for Frank Fritz tells TMZ … he died from the effects of a stroke he had several years ago -- and he had Crohn’s disease for decades, which may have played a role.

Frank was in a Quad Cities hospice (on the Iowa-Illinois border) facility and was surrounded by friends, including Mike Wolfe, when he passed.

"American Pickers" star Frank Fritz has died ... his longtime costar and friend, Mike Wolfe, confirmed.

Fritz's costar posted on social media Tuesday, sharing the tragic news with fans ... confirming the reality TV veteran died Monday evening.

He wrote ... "It’s with a broken heart that I share with all of you that Frank passed away last night. I’ve [known] Frank for more then half my life and what you’ve seen on TV has always been what I have seen, a dreamer who was just as sensitive as he was funny. The same off camera as he was on, Frank had a way of reaching the hearts of so many by just being himself."

As he continued, Wolfe remembered their friendship before filming "American Pickers" ... which documented their hunt for rare artifacts and national treasures.

He added ... "Before the show we would take off together to places we never knew existed with no destination in mind and just the shared passion to discover something interesting and historic. We’ve been on countless trips and shared so many miles and I feel blessed that I was there by his side when he took one last journey home."

MW signed off his note by sharing his love for Fritz, noting he knew his costar was now in "a better place."

Wolfe did not share any details regarding a cause of death.

Fritz's passing comes 2 years after he was hospitalized for a stroke ... which occurred amid a myriad of other health issues for the star.

TMZ broke the story ... Fritz notably stepped away from "American Pickers" back in 2021 after 12 years on the show. FF took a break from filming to deal with problems related to his Crohn's disease ... he even underwent back surgery.

Fritz and Wolfe had some estrangement at the time, with FF previously claiming his costar didn't check on him after the procedure. The pair reportedly didn't speak for a while but appeared to reconcile last year ... with Wolfe hoping to film with Fritz again.

The HISTORY Channel and Cineflix Productions released a statement: “We are saddened to share that our friend and beloved member of The HISTORY Channel and American Pickers family, Frank Fritz, has passed away on September 30, 2024. Frank filmed American Pickers for over a decade. We will always remember ‘the bearded charmer’ and his never-ending search for vintage motorcycles and bikes. Our thoughts are with Frank’s loved ones during this difficult time. He will be deeply missed.”

Fritz was 60 years old.

RIP