Start with the easy/cheap things first. Top off the coolant in the radiator and replace the cap. Bad cap may not allow coolant to travel back into the engine and radiator when it cools down.
06 Laredo - 4x4 V6 - Stone White - Custom LED Cargo Area Lights, Lighted Visors Added - now at 49k miles
97 Laredo - 4.0 4x4 Daily driver for 8 years then relocated to Arizona for 6 more years with the relatives