Q: Remove Heater Core on 2003 Lincoln Navigator

Rookie cbe0621eac06868b3efe0d8d1d3611e23c60d3114864ea2ec19a68cfbd3eebab
Do you have to take out the dash, or can you remove through the glove box area
(2) Answers
(2) Comments
There's a Technical Service Bulletin on the heater core for this vehicle. TSB # 06-21-19. Yes the dash has to come out or lifted up so you can remove the HVAC assy. You can do this yourself with the proper detailed instructions. Spend $26.95 for detailed instructions from You then will also be able to read the TSB also.
That TSB (Technical Service Bulletin) is related to electrolysis in the cooling system. In another word to much acid in the cooling system causing premature wear in the cooling system.
As the production of the model in question goes on it path of use. The manufacture sees problems that occur. So then they put out theses TSB to help their dealer techs in repairing these problems. They are not recalls that the Government mandates but just fixes for mistakes that the manufacture made. A TSB will never be a safety issue. If there is a safety issue, then it becomes a NHTSA recall. I have fixed a lot of cars with TSB's.
What does Technical Service Bulletin means: is this a recall item, or this item has alot of problems?