35D not getting up to temp

[Z06Luke]

Hey everybody, I bought my 2010 35d about 3 months ago and I've been very pleased with it so far. Today I started experimenting with the hidden menu and decided to monitor coolant temp on my way home from work which is about a 30 mile drive. The outside air wasn't terribly cold at 42 degrees Fahrenheit. My entire drive home the coolant temp sat right in the mid-sixties Celsius. I saw it break 70 one time after a hard acceleration up a Long Hill, and while coasting downhill it would drop into the fifties.

The entire 30 mile trip never resulted in a coolant temp that even reached 160* F. Do I possibly need to replace my thermostat?