Welcome to Ford40.com (or Ford 4L or Ford 4.0, whatever you want to call it.) I've been driving a 4.0 V6 OHV equipped Ranger for 10 years now and am very surprised at how little info there is on the net for this engine/vehicle combination. So I put up this site to let others know what I've learned. In those 10 years, I've also made some mods to my Ranger that would be good for any Ranger, Explorer or SportTrac with the 4L V6 engine, and I've included them as well.
Common problems and solutions:
Hesitation, sputtering, etc. - HOT!
Bad Gas Mileage
Air Box Mod for 10hp - HOT!
CAI, Cold Air Intake- actual data
Mass Air Sensor
KN Air Filter
Stealth: Avoiding unplanned meetings with Officer Friendly.
I bought the PVC fittings here.
I bought some flex PVC pipe here.
I bought my clone golf clubs here.
I bought the headers & MAS here.
I bought my truck tires here.
What I believe & why:
Disclaimer: This website is a Ford fansite. It is not authorized, nor endorsed by Ford Motor Company. No affiliatation or association exists between Ford40.com (aka Ford4L.com) and Ford Motor Company. All trademarks are property of their respective owner(s).
Overheating on the Ford 4.0L V6 Engine
If your Ford 4.0 is overheating, (or not getting up to operating temperature) first thing to do is check your radiator fluid. If it's up to level, than it's almost always the thermostat or the fan clutch. It's easy to tell which one is causing the problem: If it overheats in city driving, but not highway driving, it's the fan clutch. Easy to fix, just undue the two bolts at the top of the radiator/fan shroud, lift it up and back. This will allow you to get to the fan clutch bolts (reverse thread I believe.) Now just replace the fan clutch and reinstall the shroud.
On the otherhand, if it takes half an hour for the temp gauge to get off the "C" it's the thermostat stuck in the open position, or if it overheats in both city and highway driving, it's the thermostat stuck in the closed position. I don't know why, but at about 40K-50K miles, the factory ford thermostat quits. Either way, it's pretty easy to replace. When you replace the thermostat, you can get one from any auto supply store and it'll be a 212F termostat. If you want your engine to run a little cooler, you can get a 180F or 160F. The 180F is sold by HyperTech and the 160F sold by JET. I also found a 180F thermostat at an autoparts store while traveling. It was $4.97, or less than half what JET or Hypertech want for theirs. The manufacturer is Robertshaw and the part number is GT753-180. (See the picture below.)
Whatever thermostat you get, make sure you pick up a thermostat housing gasket just in case. It's not really a gasket, but a big O-Ring that goes around the thermostat. You might be able to reuse the old one, but it's better if you have a new one. You will need a 10mm wobble socket and rachet to get the bolts out easily. It's pretty easy if you have the right tools. If not, it'll be a "PITA." Just remove the screws holding the air channel (some people call it the "intake") by loosening the clamps at each end, and the slipping off the hose on the left side. Also it helps to remove the cover over the throttle body. Again, all these are 8mm bolts or screwclamps. Just follow the upper radiator hose down to where it connects to the block and you'll see the thermostat housing held on by 3 bolts. They are 10mm bolts. Replace the thermostat with the new one, making sure to put it in the same direction, and bolt everything back together. That should fix your problem for another 40K-50K miles.
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