Strange problem here....the brake lights aren't working, except for the third brake light above the back window - all fuses appear ok, the bulbs are fine. Is there a separate switch for the third brake light on the pedal? I can't figure this one out..

 

I think there is only one switch, however there may be more then one fuse involved... I would double check all fuses
Do you have the adjustable or non adjustable pedal ?

 

in2pro, I changed the switch on the pedal today, after I read on another forum that the third light would work sometimes when the switch was bad. Still no lights, then I saw a flicker out of one of them as my wife stood on the pedal. Investigation revealed that both light sockets were faulty and there was intermittent contact. I squeezed the contacts together a little with a screwdriver and now they work. I have had this car since new and it only has 37000 miles, I know those taillight assemblies have never been apart before. I wonder if there was a recall on this?

 

nole76,
If there is anything you would like for us to check for you in regards to your Tahoe (recall/warranty information, working with a dealership, etc), please contact us either via private message or email (include your name and contact information, as well as the last 8 digits of your VIN).

Sarah (Assisting Louis), Chevrolet Customer Service

 

nole76 good find
you may want to consider applying a lite coating of dielectric or silicone grease to the socket/bulb base to help prevent corrosion from moisture.

 

Having the exact same issue. Curious....you squeezed the contacts with a screwdriver or a pliers? I'm just trying to envision squeezing something with a screwdriver so I'm guessing you mistyped.