MustangMalo

Alright, so I have a 2002 Ford F-150 with the 5.4l triton with about 201k miles. I watch my temperature gauge frequently and today I noticed it was running just a tad bit warm, but once I got to my destination I let it idle for about 5 minutes and it dropped back down to normal. I changed my thermostat a few weeks ago due to the truck running just a little bit warm all the time and I haven't had any problems till now. Maybe I'm over thinking it because it's only a tiny bit hotter than normal but still wondering what you guys think. Thank you!

FerdinandF150

I only have experience with an older Ford over heating, but what temp thermostat did you get? How's the fluid color looking? Original water pump on it?

MustangMalo

Yeah, it has the original water pump to my knowledge. The new thermostat opens at 170 degrees. And last time I changed my coolant (when I changed my thermostat) it was almost light brown and green. Thanks for the reply

FerdinandF150

I'm not sure how many miles ago all of that was, but when the fluid in my old ford started to brown ( it started out green) it was time for a new radiator. The core was rusted. How's the condition of the radiator look? Both bumper and engine side? Any flakes in the coolant if you were to check it out today?

MustangMalo

Yeah I was thinking the cause of the brown color was rust. No flakes when I changed it about 300 miles ago, I'll be sure to check to see if there's any. What would be causing the flakes?

FerdinandF150

The flakes in mine were rusted metal coming off the core of the radiator. It was a 1970 afterall. You should be able to, when the truck is cold, open the radiator cap and look down inside and see the radiator core. You should also be able to start the truck and see the fluids flowing. A lack of flow would be a clog, did you flush the system or just dump the fluid and refill?