Temp Gugage?

I’m a bit confused?? Why would my temp gugage on my 2005 1500 Dodge Ram Cargo van stay cool when going slow (city streets) and get hot on freeway when moving faster. Both time air is on?

Is the engine actually overheating? Have you checked the coolant level?

The more gas the engine uses, the more heat it cranks out. This sounds like an air or coolant flow problem. Check the front of the a/c condenser for a buildup of leaves and bugs. It could also be a problem with the radiator caap.

No it’s not over heating…it just starts to climb near 210 real fast…and it concerns me. The coolant level in the over flow is 3/4 full. I’ll check the cap as well.

There are several possibilities. How many miles? It is not likely you would have enough miles yet, but a worn water pump can do that.

Poor coolant flow. The passages might be scaling. At low speeds, there is enough flow, but at high speeds, the engine is working harder but flow isn’t keeping up. Time for a serious flush?

It could also be as simple as a sticky thermostat. Being as cheap as they are, that’s usually the first thing to check…or simply change.

A sticky T-stat could work in two ways. It could be not opening all the way, enabling the engine to run hot on the highway, and it could be not closing, preventing the engine from getting up to its operating temp. It could be stuck 1/2 open!

Yep, add thermostat to the list.

Radiator clogged with leaves or other debris? Hose collapsing? It does not seem like a 2005 should have scaling problems already unless someone is running water instead of coolant.