08 gmc key programming

Can anyone tell me the proceedure for programming a new key to an 08 GMC Sierra... I have two programmed keys now and will use one for the key in a box for the remote start.. Thanks in advance

Check your key for a "PK3" or a + sign inside a circle.  If either of these are stamped on your key blade, here is a link to the programming to add another key :

http://aftermarket.strattec.com/docs/On%20Board%20Programming/On%20Board%20Programming%20%201.pdf

Replacement keys are available for around $12.

Soldering is fun!

Sorry, don't know why that link isn't working.   Here is the write up:

Important:

• To initiate, this procedures requires that a learned master key be available. • A total of 10 master keys or valet keys may be programmed to a single vehicle. • This procedure adds keys only. The procedure does not erase previously learned keys. • The keys to be learned must duplicate the mechanical cut of the current key. • If more than one valet key is to be learned, immediately precede each valet key with a learned master key.

1.)  With a previously learned master key, turn ON the ignition, with the engine OFF. Turn OFF the ignition and

       remove the key. 2.)  Within 10 seconds insert the key to be learned. Turn ON the ignition with the engine OFF. The vehicle has        now learned the new key.

Soldering is fun!

if you want to use an uncut key( for more security) after wiring remote start and verifying it works with one of your existing keys in ign when starting,turn existing key in ign on until theftlock light goes out, then turn ign ofrf, insert blank uncut key into ign barrel and remote start vehicle, will program it