I have a 2003 -2500 HDSilverado with a Duramax Diesel. I am having trouble with the exterior temp gauge that is on the mirror. It has always worked properly until about 2 weeks ago when I put on the cold weather front. (Live in MN). In the past when I put the front on it would vary the temp gauge about 2-4 degrees above actual temp. This time it is reading 40-50 degrees when the actual outside temp is about 10-20 degrees. I have a couple friends with the same truck and they say the cold weather front affects their gauge by abot 3 or 4 degrees. Any suggestions?

 

Yeah. The sensor is in front of the radiator. You're making the heat from the radiator build up where the temp sensor is. Nothing you can really do, take the apron off the front and it'll work fine.

 

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