Radiator Thermostat problem ?

[Slopeflyer]

Drove the truck 30 miles today most of it on the freeway at 70 mph with heater on high. When I got home I popped the hood and felt the top Radiator hose it was hot. Went under the truck and the lower radiator hose was cold. Took the radiator cap off felt coolant it was cold. Outside Temperature was 58 degrees. The dummy water gauge in truck said it was not running hot. Truck ran great. Is there a problem with my Thermostat or am I just worried for nothing.

[Ressurektion]

Sounds to me like a thermostat stuck open.

If it's been a while, wouldn't hurt to replace it with a known "good" stat.

Had pleanty of farm tractors with that problem. Sucks changing one with snow in the field.