2000 Ford F-150

Engine Cooling problem
2000 Ford F150 6 cyl Two Wheel Drive Manual 102000 miles

My problem is that my Ford is overheating when I'm going more than 50 mph. But when my truck is idling it goes back to normal or when I turn of my truck and just let it sit for about 5 min its fine. I just replaced the thermostat and flushed out the radiator. What else could it be. Please help!
November 18, 2009.

That is usually the opposite of what happens. Have you had to add coolant? Have you checked the oil to make sure the coolant isn't making its way to it? Also, how does it run other than the overheating? Finally, how old is the lower radiator hose? I have actually seen them collapse when the engine reves. At highway speed, the engine is reving and it could happen.

Let me know.

PS: Are you sure you replaced the t-stat facing the right direction?

The truck runs fine. I haven't had any problems with it besides the overheating. I did put the t-stat facing the right way. I haven't changed the lower hose since I got the truck, that was 3 yrs ago. The truck only had 66k. My friend told me that its the radiator, that is is clogged. Let me know if that sounds right!

Nov 18, 2009.
That could be the problem. You can try to flush it yourself. If that doesn't clean it out well enough, have it rodded out. They will actually place the radiator in an acidic solution that will clean it out. There is a place near me that does all my radiator work. WHen I get it back, it is cleaned, repainted, checked for leaks, and looks and works like new. And all of this is done for around 40 dollars.

THat would be a good idea to try. If the hoses are old, it would be a good time to replace them too.

Let me know what you find.