Noticed on Monday when we were hauling around some landscaping supplies that the Ranger was getting way hotter than usual. Took it very easy on the way home and rode with the heater on high for the 10 mile ride home in the 90 degree weather without it overheating but knew something was wrong. Stopped Tuesday at the dealer and ordered some parts and got them on the way home today....new Motorcraft thermostat & O-Ring and an upper & lower radiator hose just for good measure since I was going to have to drain the coolant anyway. Also got another gallon of Zerex Z-05 at the local Napa. I had just flushed and changed all the coolant last fall so it was still good but as usual I manage to spill some no matter how careful I am.

The thermostat is a real piece of cake to change out on the 4.0 SOHC...very suprised. I simply unbolted the air intake hose, throttle body, and got out the 3 bolts for the housing....no problem. It's a little tricky to fit back in its spot and you have to have the thermostat oriented the right way to get the housing to fit back right. Dumped the coolant into a bucket, pulled off the OEM hoses (which really were still in decent shape) and installed all the new stuff. I filtered the 6-month old coolant through some cheesecloth while pouring it back in, topped it off, let it run, heat up, drove it, topped it off again, let it run some more, cleaned everything up and all is fine now. Lost an original OEM battery earlier this month and now this but not bad for being nearly 8.5 years old. Currently have 61K on the odometer.