We dropped off the trailer, but the engine was still really hot, got a light saying check gauges?

When the engine was hot did you hear the clutch fan kick in? (Airplane sound) if not, the clutch fan is not good and needs replacement here is how to change the parts out and this guide can help as well. Make sure you use a high-quality replacement, (name brand).

https://www.2carpros.com/articles/engine-overheating-or-running-hot

And this video as well:

https://youtu.be/N_-MLVlBHk8

Check out the diagrams (below). Please let us know what happens.

Yeah, clutch fan is fine.

We also tried to replace the sensor but it’s still the same.

I would change out the thermostat and service the cooling system. Also, check for obstructions in front of the radiator such as a plastic bad, etc.

https://www.2carpros.com/articles/coolant-flush-and-refill-all-cars

Check out the diagrams (below). Please let us know what happens.

Yeah, it was the thermostat we are going to get a new radiator and all good Cummins parts for good measure.

Good to hear, please use 2CarPros anytime we are here to help.