With 5w40 mine tends to sit around 30-35 hot idle, 40-45 cruising, and pops the bypass open around 55-60 at wot. Cold it runs 60-70, never seen it go over 75. I know early trucks(01-02) tend to read higher as the sender is located up front right next to the pump, later trucks(03+) tend to read lower since the sensor was moved furthur away and after the filter iirc. I need to replace my sender as I know it's off some. It shows aroind 35-38 when the squirters open, but I believe they actually open around 30-32 for early lb7's if i read the specs correctly.