Temperature gauge shows tahoe is running hot but radiator coolant is not hot

the thermostate coul dkeep the water in the engine to show hot if the wtsu is also in the block...first check the wire/s on the sending unit..then replace water temp sending unit..also check and replace thermostate ALSO CHECK AFTER RUNNING IF THE LOWER RAD.HOSE IS SUCKING CLOSE...GMS DO THIS..

Okay thank will check! I appreciate it.