run the truck and use the wifes candy or meat thermometer in the rad to compare - or if the truck isn't running, dunk the sender in boiling water and watch the gauge, use the thermometer to compare gauge reading to water temp as it cools

Bill


Moved over to the Passing Lane

"When we tug a single thing in nature, we find it attached to the rest of the world" ~ John Muir
"When we tug a single thing on an old truck, we find it falls off" ~ me
Some TF series details & TF heater pics