Programming 'auto-unlock' Without Dic Customization

[MoDaddy]

Just bought a 2008 Sierra 1500 Work Truck.

Auto-unlock of all doors activates every time you put shifter into Park.

This is very unsafe! (especially in our neighborhood.)

My trade-in (2002 Siverado) was programmable.

Sierra WT appears to not be as it doesn't have DIC Customization.

How can I defeat the auto-unlock?

[Darkanion]

I'm not sure if this will work on the 2008's. Try this thread, though :

http://www.gm-trucks.com/forums/index.php?showtopic=44563

[Gray Ghost]

BUy the DIC center computer and dash panel for $81.00 at gmaccessoriesstore.com and then you will have access to everything. Even change the chime volume.