Nah, I tried that...

There isn't even anything in (port 8 I believe) I tried that.

Check this site. It has free programming directions for lots of vehicles.
Free Keyless Remote Fob Entry programming instructions, procedures for all automotive vehicles

Appreciate the help, but it's not like I'm doing the procedure wrong.

I'm just convinced the truck doesn't have the option for some gay reason

Programming the key fob
 

Hi Guys,
I got this from my 1999 Silverado owner's manual:

"To resynchronize your transmitter, stand close to your
vehicle and press and hold the LOCK and UNLOCK
buttons on the transmitter at the same time for seven
seconds. The door locks should cycle to confirm
synchronization. If the locks do not cycle, see your
dealer for service."

Also the manual says the battery is a CR2032 3 volt.

Hope this helps.

i'm working on a 99 gmc z71 that doesnt have anything in port 8 or 1 wtf ?

I am also having an issue programming my remotes. I tried holding down the unlock button and cycling the ignition (on-off-on-off. Nothing. I tried the jumper wire way but my ODB2 port does not have a tab in the #8 spot. What now???

1. Start with ignition off.
2. Press and hold unlock button on drivers door, the locks will cycle once.
3. Turn ignition on-off-on-off.
4. Release unlock button, the locks will cycle once.
5. Hold down lock and unlock keys on keyfob transmitter until locks cycle (about 15 seconds).
6. Repeat step 5. for remaining keyfobs (up to 4 total)
7. Turn ignition on to exit the programming mode. Programming is now complete
On step 5 you have to hold down the unlock and lock buttons on the remote at the same time till you see the doors lock then it will be complete.........
I just reprogramed my 99 xcab remote with this procedure and it worked
Hope this helps......

The above instructions were the ones I used. I don't have a 99 xcab just a 3 door 99 Silverado
Also when I did mine it took up to 30 seconds for it to program while holding the key fob buttons.
I also thought I was doing it wrong but by holding both lock and unlock buttons, which seemed like forever, it finally programmed.

StI'll doesn't work
 

Did everything. Even held the remote buttons for a full min. Still nothing.

I'm having the same problem did you ever figure it out please let me know thank you

<br />I'm having the same problem did you ever figure it out please let me know thank you