it should be on block under the oil pressure sensor it has one wire that pushes onto it like the oil pressure sensor that is above it. you should have a mechanical type fan on this truck so you will generally only have one coolant temperature sensor/switch. only / mostly electric run engine cooling fans require/incorporate the use of two seperate t.c. sensors/switches one generally goes to computer for fan control at certain temperatures and basic engine management and the other is for ur gauge.