Fans of Adam Carolla’s classic “Loveline” radio show know who David Alan Grier is.

Many recall the comic actor from his “In Living Color” days. For “Loveline” listeners Grier became one of the show’s most memorable guests. His goofy, stream-of-consciousness rants left Carolla and co-host Dr. Drew Pinsky in stitches. Grier continued appearing with the radio personality on “The Adam Carolla Show” podcast. Carolla even cast him in his 2015 indie comedy “Road Hard.”

That was then.

Grier hasn’t been on the “Carolla Show” in some time. And we recently learned why. The comic actor, who like most entertainers leans hard left, called Carolla a “right-wing troll” on “The Howard Stern Show.”

“Adam and I were quite close,” Grier told the SiriusXM jock.

“What happened?” Stern asked.

“He’s a right-wing troll now,” Grier said. “I just can’t hang out with him anymore. I cannot. I cannnnnnn’t. No … go do your thing. I just don’t wanna be a part of it.”

Carolla’s main messages are cultural in nature.

Go to school

Work hard

Study hard

Have kids later when you’re finances are solid

Don’t covet your rich neighbor

Work harder than him or her

Carolla’s mantra hasn’t changed over the years. His podcast veers into political territory now and then, and he often embraces a libertarian mindset.

He’s darn near impossible to pigeonhole, politically speaking. He’s best chums with conservative talker Dennis Prager, but he’s an avowed atheist. He believes firmly in free speech, and he’s also socially liberal on most issues.

He’s no Trump apologist, either.

That wasn’t enough for Grier, apparently. Carolla addressed the issue on a recent podcast, saying he wasn’t even aware of the rift between the two former buds.

“People keep saying, ‘why isn’t DAG on the show?’ I don’t know,” Carolla said to introduce the subject. The podcaster gently called him erratic, but not in a way that would cancel their bond.

“You don’t talk to him for three years and then you talk to him,” Carolla said, while the show’s sound guru Bryan Bishop played funny DAG clips from past appearances.

Carolla didn’t attack his former friend.

“I’ve always attempted to be a part of his life,” Carolla said, ticking off times he invited him to both personal and professional events. “I’ve never been overly generous, but I”ve always been very friendly and never had any ill will.

“I don’t feel like I need to reach out and fix things because I don’t think I broke things. I’ve always been around and open to having him on and socializing, doing whatever may be,” Carolla said.

It all comes back to Trump, he said.

“Trump got elected, and there’s two sides of this world now. You have to be completely outraged that he’s president and been going nuts on him, or there’s my side, which is I get the f— on with my life and we’ll see what happens in two years … and if you’re on that side, not part of the Resistance, you’re part of the occupying force,” he said. “I’m not, but that gets me into the group that’s occupying Poland, except I’m not in the army, I’m a citizen and I’m not picking up a pitchfork.”

Grier followed his Stern show confession by describing an encounter with one of his fans. The person railed against Grier for his liberal politics, but Grier gently responded that they could disagree politically and still be friendly.

Stern co-host Robin Quivers quickly noted the double standard, since Grier is no longer friends with the right-leaning Carolla.

“F— no. Do you practice what you preach?” Grier said in response.