Re: Ford Thermostat info.
The thermostat is more oriented to vehicle emissions than best performance. That's why underhood temps keep climbing over the last 10 years. Most vehicles will benefit from 185 if they ping on premium or mid-grade gas. Also, thermostats do not operate full open all the time. They respond to engine temps. The ones that open sooner do keep the temp down. People I know with regular temp guages in their Fords show lower all around temps, and that translates to longer oil life, coolant life, belt and hose life, a few more HP and a 0.5 MPG increase.<br /><br />Be warned that the 180 may keep the motor cool enough that the computer thinks the car is still warming up and keeps the fuel enrichment on. I have heard his warning but never met/read about anyone that actually experienced it.<br /><br />For the $10 or so bucks it costs to change, it is worth trying it out if you are interested.<br /><br />One more thing. If your temp guage normally fluctuates while operating the vehicle, ex it rises at traffic lights and drops when the fans kick in, then you will see lower temps register if you change the t-stat. If your temp guage rises to the same place and is rock steady the entire time you operate the vehicle, then you will not see the temp drop when the t-stat is changed. That is because the latter guage is not a true temp guage, but a cold/normal/hot indicator that cannot register the 5* change by the new t-stat.<br /><br />I run the 185 in both my Town Car and Mountianeer. Both perform better with the lower temps.
