I ask for your help for thermostat

My friends vehicle 1.4 sedan in the city heavy traffic, the heat turns on at 95, the fan turns on at 95, but when I go to the long road or the ring road, it falls down by 60 degrees and stays there. Gates brand thermostat is very bad, I have it, if you say it's bad, what other brand should I buy? I would be very happy if you share your information Emrah206sd 2019-12-04 23:37:55

your thermostat works just fine

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