Changed my radiator a few months back. Coolant level held steady since. Have been checking once a week or so and level stayed right at cold fill line, have also been checking in around 70 to 95 degree weather. This morning I check it and notice it is about 1/8" below cold fill line. It was 35 degrees this morning. After truck is up to operating temp and shut down it is back at cold fill line, after cooling off at 40 degrees now it is back 1/8" below line. Should I top off or leave it be? Could the temp difference have and effect? Thanks for any ideas.

 

You can add some if you want. If you have too much it will purge it

 

Thats what Im going to do to cater to my OCD lol