[Chrysler300] 61 300G heating i have had mine 54 years. Yes they come with too small of a cooling system for this day and time. Igot in a traffic jam on the interstate for an hour 101 degrees f. she melted down with the air cond. off.I RUN A 160 DEGREE THERMOSTAT IN THE SUMMER AND A 180 DEGREE IN WINTER. LARGER RADIATOR WITH ONE MORE ROW OF COILS. PROBLEM SOLVED! YOU CAN'T GO BY THE GAUGES ON THE G MINE IS NOT CORRECT.TO START WITH THE PROBLEM.YOU GET a THERMOMETER AND CHECK YOUR GAUGE WITH IT .YOU CAN GET A INFRARED-LASER THERMOMETER HAND HELD . AT HARBOR FREIGHT FOR $26.00 TAKES THE GUESS WORK OUT. HOPE THIS IS HELPFUL