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High mount 3rd brake light leaking TSB

Discussion in 'Chevy Silverado Forum (GMC Sierra)' started by the phantom, Dec 17, 2013.

  1. the phantom

    the phantom Active Member 2 Years ROTM Winner Gold Member 1000 Posts

    Just thought I would give a heads up on an issue I had a some months ago and would share with my fellow truck owners.

    I had replaced my stock 3rd brake light with a smoked out one to go with my theme for my truck. Well after about 15 months I notice one day my remote key fob wasnt working and the tps monitor indicator in the DIC was lit indicating a problem. Then for the next month everything worked fine. Then again one morning I noticed the tps monitor indicator was lit again so I drove right to the dealership. They took it right in and 2 hours later came out and told me that my 3rd brake light was leaking water and it found its way to the module that runs the tps (wireless)system and the key fob remote (wireless) thats located I believe in the driverside rear cab post.(basically where the rear door latches) The mechanic came out and kinda gave me the speel of "I see you changed your third brake light to an aftermarket one" I said "yes I did but I used the same seal that came with the stock one." He replied with "well we are going to cover the repair because there is a technical service bulletin out on the stock 3rd brake light possibly leaking and causing this issue." I was relieved and said ok cool. Well after seeing the silicone he smeared on my roof I was none to impressed but I believe the module was about $700. So as we are getting to the point of the 2011's warranty's expiring, Its something to think about.. Also Im not sure what years or trucks are affected by the poor design of the seal for the 3rd brake light but when I originally removed it I did notice it was not the greatest of seals. Maybe some searching can find this TSB and will give more detailed info about it. Hope this info can save someone some headaches and $$$$$$$.
     
  2. j cat

    j cat Rockstar 4 Years 1000 Posts

    so with what you clearly described is your work was the cause of this leak.

    this seal should be replaced or what I would do is get some clear silicone sealer and coat the cheap GM gasket . not too much ,,, then let is sit for 45 min . then install the light. that way is will not get all over the vehicle but still be soft enough to provide a good seal.

    when you work with old vehicles with these issues this is what is done. seals are hard to find and very expensive .

    being where its located I have heard many with this failure and they did not mess with it .

    you lucky they did not charge you. if the 700 dollar part blew up you bet you would be paying for that.
     
  3. the phantom

    the phantom Active Member 2 Years ROTM Winner Gold Member 1000 Posts

    Clearly you did not read my post very well. I put the original GM seal onto my new aftermarket light as it was on the stock light. The stock light is known to leak so a tsb was put out to put silicone around the seal with the light in place. The GM mechanic did this getting silicone all over my roof. I agree with your method of applying the silicone but because I did not do this is not my fault because it originally was not done this way. Had I seen a tsb on this I wouldnt be writing this thread. And also the $700 module did blow up and they did replace it under warranty.
     
  4. j cat

    j cat Rockstar 4 Years 1000 Posts

    when you disturb these seals exposed to sun light and use a different light fixture then this will leak especially if it is a known problem.

    from what I read they just used sealer to stop the leak . not clear that they replaced the 700 dollar module.

    I still think your very lucky they covered it since you changed the light out with an aftermarket one.

    could be GM CEO is changing how customers are treated . I was at the dealership today and they are very helpful suddenly.

    I was going to remove my 3rd light , but changed my mind when I saw the seal used .
     
  5. the phantom

    the phantom Active Member 2 Years ROTM Winner Gold Member 1000 Posts

    I understand what you mean by disturbing the seal but if you would have seen this seal when I took it out with the truck having 150 miles on it and brand new. I feel it would have leaked anyway the way it was in there when I pulled it out. This seal was a foam rubber seal with no glue,sealer, silicone of any sorts on it. The sun had not yet done anything to it, infact it was more behind the light than not, where the sun really doesnt get to. So its not clearly my work that caused the leak it would be clear that the original stock seal is of poor quality due to this being a known issue before such seal is even disturbed with the stock light.(The whole purpose of this thread)All they did was seal the entire gap from the light to the cab with clear silicone (would have much preferred your method)and replace the module(this is how I knew the price of it because they replaced it.)They also had to reprogram the TPS and the Key fob remotes after changing the module(which I didnt mention earlier). The dealership I am dealing with (not the dealership I bought from) will do what they can for customers with aftermarket products on the truck the best they can. Because this issue was common with the stock light they were able to get this covered by GM without any issue. So why shouldnt a dealership do this for potential future customers? Customer service regardless of where a vehicle is bought is a way to generate future business relationships. Unfortunately this dealership couldnt get the truck I wanted at the price I paid but Im still giving them business regardless if its warranty work or not. So after learning of the stock one having this problem my opinion is they are lucky they covered it IMO.:lol:
     
  6. j cat

    j cat Rockstar 4 Years 1000 Posts

    I can see why your concerned about the future with this issue. if it leaks again this can be a very expensive repair.

    I have had issues with defects in my truck that the dealership tech messed up on . after the warranty ends its all over if their repair screws up. then they blame GM . call GM they blame the dealership. I loose.

    on one issue I had , GM stalled a widespread defect that was common , took 10 years going thru the court system . GM still one in the end , because few could collect on the repair costs made....
     

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