"Rush Hour 4" is off to the races ... pre-production is starting within weeks, cementing Brett Ratner 's return to Hollywood, TMZ has learned. Understand the words comin' out of our mouth ... the fourth installment in the popular franchise starring Chris Tucker and Jackie Chan was greenlit last November -- shortly after President Trump randomly said he missed old-school buddy-cop comedies ... specifically saying there needed to be another 'Rush Hour.' A source with direct knowledge tells TMZ … '