Jfg1300

Hello I am new to the Forum but I currently have a 2020 2500hd with the duramax. It is my third diesel and the 2020 seems to have a much lower operating temp according to the gauge. It fluctuates between 170-185 Approximately. The previous 2016 I had was very consistent running just below 210. I have asked dealer if it’s normal operating temp? Gauge issue? I am only concerned to make sure engine is at proper temp for emissions etc. any info would be great thanks