The Rock and Vin Diesel have buried the hatchet and both will star in the next installment of the insanely popular 'Fast and the Furious' franchise ... sources involved in the production tell TMZ.

Our sources say Vin and Dwayne have met privately several times since animosity between them exploded on the set of "The Fate of the Furious." We're told they are "good" and both are "1000% in" for the next flick.

The sources are opening up about the feud ... one explaining it was all over "real estate." In movie language, real estate is all about how much an actor shines -- who gets the best action scenes, who gets the hottest girl, who shows off their body more, and who gets the most face time.

It became a big issue for Dwayne and Vin, but ultimately, Dwayne acknowledged it was Vin's movie -- he's listed #1 on the call sheet.

The one thing the feud was not about ... money. They both make a fortune off the franchise.

But all systems go for the next installment.