My 2018 F150 3.5 Ecoboost engine temperature has always run between about 207 and 217 degrees Fahrenheit. I just had the cam phasers and all timing components replaced at 99K under warranty and want this engine to live a long life. Since I hit 100K recently and am now out of warranty I decided to install a 180 degree Motorcraft thermostat.
These are my observations…
I placed both the old 195 and new 180 thermostats along with a temp gauge into a pot of water on the stove. I had to wait for my wife to run some errands to complete this mission as she would kill me if she knew what I was doing with her cookware. I won’t mention the time that I washed Harley cylinders in the dishwasher… Hahaha, good stuff. Anyways, the 180 unit started opening about 185 and was fully open by 195. The 195 unit didn’t start to open until just past the 205 mark.
I ended up reusing the factory O-ring on the new thermostat. I had picked up a Felpro O-ring but the Ford part was way better in the way it’s made. After installing the 180 thermostat and topping off with proper coolant I went for a test drive.
I immediately noticed that the engine temperature was running 15 – 20 degrees cooler. An unexpected benefit was that the transmission temp was also running cooler as well. I always thought the tranny had a thermostat that kept it at 200 but it’s now running about 190 when fully warmed up,
I ran the interstate at 55mph and then at 80mph for a bit. I never saw the gauge run over 203 even when running hard up the hills.
I should have done this when I first bought the truck 50K miles ago but I didn’t want to touch anything for warranty purposes. I'm picking up a small travel trailer soon and am glad I did this mod before towing it.
Here are a few pics including the new stat and my shakedown run temps.
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These are my observations…
I placed both the old 195 and new 180 thermostats along with a temp gauge into a pot of water on the stove. I had to wait for my wife to run some errands to complete this mission as she would kill me if she knew what I was doing with her cookware. I won’t mention the time that I washed Harley cylinders in the dishwasher… Hahaha, good stuff. Anyways, the 180 unit started opening about 185 and was fully open by 195. The 195 unit didn’t start to open until just past the 205 mark.
I ended up reusing the factory O-ring on the new thermostat. I had picked up a Felpro O-ring but the Ford part was way better in the way it’s made. After installing the 180 thermostat and topping off with proper coolant I went for a test drive.
I immediately noticed that the engine temperature was running 15 – 20 degrees cooler. An unexpected benefit was that the transmission temp was also running cooler as well. I always thought the tranny had a thermostat that kept it at 200 but it’s now running about 190 when fully warmed up,
I ran the interstate at 55mph and then at 80mph for a bit. I never saw the gauge run over 203 even when running hard up the hills.
I should have done this when I first bought the truck 50K miles ago but I didn’t want to touch anything for warranty purposes. I'm picking up a small travel trailer soon and am glad I did this mod before towing it.
Here are a few pics including the new stat and my shakedown run temps.
