Quote Originally Posted by LeMarky Dissod View Post
Those fan-on settings are too cold for any thermostat, even the 160°F thermostat. Once a thermostat opens it should not open and close chronically; it should open wide and stay wide open til the powertrain is done working.160°F thermostats are fully closed below 160°F, and fully open by about 176°F.
If you want the fans CONSTANTLY on for some strange reason? Fan-OFF @ 160°F or less.

With a 160°F / 71°C thermostat:
Set the Fan-OFF @ 176°F / 80°C. Any lower and the thermostat will stutter.
Set the Fan-ON @ 185°F / 85°C. This might let the fans shut off while the vehicle is moving fast enough to do the fan's work for them (45MpH or more).

Be sure the radiator (and external ATF cooler if also equipped?) are getting as much airflow into them as possible so that the fans' work is made easier.
Check your baffling, and consider adding coroplast in choice spots if need be.
Too much of a temperature cycle when you stop for me. With a 170°F thermostat my low speed comes on at 178°F and I have it set to turn the fans off at 176°F. I keep the on/off settings close because once the water starts to cool off at the coolant temp sensor the fans have already run long enough. It tends to run within a few degrees of 180. Like 178-182°F.