Just finished up a oil change this past weekend. Looked over everything when putting oil in the truck. I noticed my coolant in my over flow tank is barely under the cold fill line. My questions should I even be worried about this? If I need to fill it a little, do I add just distilled water? Just concentrated gold coolant? Or a mixture of both? Thanks for the help..

 

Wouldnt even worry about it.

 

If you have a 2010, you should probably consider getting it flushed and replaced. If it's barely low, water would be fine.