I own a 2009 chevy tahoe hybrid with 55k miles. the front and rear door lock actuators failed one at a time from the rear passenger to passenger to drivers side of the truck from 36k until now at 55k. the faulty door lock actuators prevent locking or unlocking of the doors from the drivers seat as well as with the remote. when the car is put into drive, all the doors are supposed to lock. this no longer happens due to faulty actuators. as i have small children, i feel it is a safety issue to drive with unlocked doors. after researching this issue i have discovered the problem to be widespread on a number of chevrolet vehicles. please reference the following internet forum discussions : http://www.gm-trucks.com/forums/index.php?showtopic=98284&st=165 and http://townhall-talk.edmunds.com/direct/view/.f206d4b/75#msg75 i suggest the nhtsa look into this issue and mandate the installation of a more reliable door lock actuator and replace the existing faulty ones. i contacted my local chevy dealership and asked if they could replace them (at no cost to me of course). the service manager stated that he replaced a number of them already. he also stated that chevy may pick up the cost "depending on if i service my car there and if i have a history of buying chevy products". i really don't think they care about the safety issues this causes. if i can be of further assistance in this matter please let me know. thank you! *tt