06 buick lucerne floor shift Won’t move in drive

Hello, the shift lever should lock in the Park position, and should not be able to be moved out of "park" unless the brake pedal is depressed. I'm concerned that perhaps the shift lever linkage is not accurate, or the shift lever position sensor may not be operating properly. A diagnostic tool will be able to see what gear is being selected by the shift lever, versus what position it is in. You may find this is the area to look into, more than fearing the worst of a transmission engagement concern. Use this link to find some shops near you that can help with your concern: www.repairpal.com/repair-shops