Intermittent heat in cab and temp gauge fluctuating

I thought I would share an experience I just had real quick in-case it can help anyone else. I have a 2014 4x4 Limited with about 140K miles on it. I had an oil change and tire rotation done about 2 weeks ago at the local dealer. They commented on how great the truck looks for being 10 years old. Other than the flex fuel alcohol density reading / hard start problem, I've had no real major issues and the truck runs great. I tow an RV trailer with it frequently.

Over the course of the last few weeks I noticed the heat would come on and go off and when it came on, it smelled off, like weak body odor or something like that. My immediate thought was that the heater block was clogged but I've had a coolant system flush done in the last couple of years. As I continued driving it a few days later I noticed the temp gauge moving hotter and back down. For the most part the thing is usually stuck on just less than half, so any movement is odd. The next day its moving farther to hot and then back down. I checked the coolant and it appeared fine. It was so bad yesterday that I took it in first thing this morning and on the drive over, it was so close to hitting red, I thought maybe I should have towed it there instead of drove. Anyhow.... long story short, it was the radiator cap. When they looked at it, it fell apart in the techs hands. They put a new one on, added more antifreeze, and bled the system and that resolved the issue. I can't believe I didn't put 2 and 2 together myself quicker but I'm thinking heater block, water pump, bad temp gauge....not the cap lol. I'm just glad it ended up being the least expensive thing and the head gasket wasn't damaged.

 

Thanks for the post. Seeing how some of the radiator caps are falling apart I purchased a new one to replace my 2016..Thanks..