SOHC 4.0 thermostat housing upgrade

[twoll86]

The SOHC 4.0 in the Ranger (and I believe the explorers) came with a plastic thermostat housing that is prone to fatigue and failure. Well mine failed last week in my search for the best price on a replacement i came across a SPK part on rockauto that is Aluminium. It comes with new sensors and and thermostat. For around the same price as the oem part

 

[sgtsandman]

I’ve done this upgrade. Not cheap but better to do “one and done” than replace the plastic housing over and over again over time.

The one I ordered was for a single sensor with a plug in the unused hole. It also came with all the needed o-rings and gaskets to do the swap.

 

[gw33gp]

I have only replaced my original one once in the 251K miles I have driven it. I would have considered going to aluminum if it had been available then. One thing to know about aluminum is it can corrode, so make sure you keep the coolant within its usable time.

One thing I have heard about the aluminum thermostat housings is a porosity issue on some that cause leaking with time. That may have been on the early ones and not an issue anymore.

 

[purojekuto]

I just replaced my thermostat housing. My original part lasted 350,000KM. I saw the aluminum one on eBay as an option but decided to go with the $43 plastic aftermarket kit from RockAuto instead. Only time will tell if I will kick myself for that, but I think it will last until my poor truck heads for the junk yard.

 

[twoll86]

I just replaced my thermostat housing. My original part lasted 350,000KM. I saw the aluminum one on eBay as an option but decided to go with the $43 plastic aftermarket kit from RockAuto instead. Only time will tell if I will kick myself for that, but I think it will last until my poor truck heads for the junk yard.

This one was only 40 on rock auto but one of the sensors were wrong for my application. No biggie mine were fine.

 

[Otis413]

I just ordered one without sensors (has the places for two) for $26.79 (SKP SKRH144C) for the motor I'm rebuilding for an 03 XLT. I'll post back a review once I get and install it.

RockAuto | All The Parts Your Car Will Ever Need

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[sgtsandman]

So far, everyone who has gotten one hasn't complained. Mine works just fine.

 

[PetroleumJunkie412]

the motor I'm rebuilding for an 03 XLT.

Dear God man, youre brave.











I also have one on my 2011. Seems better.


Motor is still a turd, though.

 

[Otis413]

A little update; I got my new thermostat housing (no sensors, SKP SKRH144C) today. It seems very well made, but.... The openings for the sensors on the new housing are a little larger then the OEM housing, 0.530: Vs 0.505" The OEM sensors with their old flattened out O-rings just drop right in, so new O-rings are a must (I'm guessing oversized) It came with two plugs blocking the sensor holes, the o-rings on the plugs fit but not very tight, I'm not trusting them. Also the clips holding the plugs in are made of smaller dia wire and aren't as strong, you'll want to use the OEM clips.
All in all I'd recommend getting the one with the sensors already installed.

 

[cbxer55]

I just did my 4.0 Mustang on Saturday. The plastic one was leaking bad, made a mess of the underhood area. I got a link on Stang.net for this part. It only has one sensor, the other outlet is cast over during the making of the part. Uses o-rings and gaskets together for a much better seal. Drove it quite a bit after the install, no leaks. I had been running a ten pound radiator cap while I was searching for the leaks cause. I'm back to a 16 now.

2005-2010 Ford Mustang 4.0 V6 metal thermostat housing

 

[cbxer55]

Oh, I also dropped the thermostat from the stock 192 to 180. It's reflected in the gauge, with the needle not making dead center any more. Like my other two Fords, I can tell when the thermostat opens on them all, the needle drops some then returns. Also, on all three, when I turn the heater on, the needle drops noticeably. Especially the Mustang, if I turn the heater on full bore, as I like to drive with the windows down and the heater blowing, the needle will drop way over to the left and even stay there until I turn the heat down.

 

[DILLARD000]

Looks identical to the Aluminum ThermoStat Housing that I put in my 2001 V6~4.0L~SOHC a year plus ago.
Modified it by moving\changing the Left\Gage TempSensor, for better access to the TimingTensioner.
The factory plastic & like replacement housings from the local parts counter are true junk.
I'm happy with this aluminum upgrade. Details here

Engine Coolant ThermoStat

In early 2019 & 19+ years, the FactoryOE ThermoStat Housing on my 2001 Ford ExplorerSportTrac started to leak per the pics below; at first just an irritation, this leak steadily grew much worse. Under the Throttle on the V6~4.0L~SOHC engines TopFront in several 1997~2012 models, the FactoryOE...

2001fordexplorersporttrac.fandom.com

 

[DILLARD000]

...dropped the thermostat from the stock 192 to 180. It's reflected in the gauge, with the needle not making dead center any more. Like my other two Fords, I can tell when the thermostat opens on them all, the needle drops some then returns. Also, on all three, when I turn the heater on, the needle drops noticeably. Especially the Mustang, if I turn the heater on full bore, as I like to drive with the windows down and the heater blowing, the needle will drop way over to the left and even stay there until I turn the heat down.

@cbxer55
I've also "experimented" with several thermostat valves rated at lower temps.
~ 192f89c Ford\MotorCraft#rt1167 FactoryOE ran with the GageNeedle@50% steady.
~ 174f79c Stant#13648 ran very notably cooler with the GageNeedle@40%, but was unstable opening & closing as you've described.
~ 190f88c Stant#13649 ran just slightly cooler with the GageNeedle@50% steady.
~ 183f84c Stant#14748 runs notably cooler with the GageNeedle@45% steady; this is what I've settled with.
WARNING: the Stant#14748 if used "as is" WILL GET STUCK OPEN as the lower ByPass disc will jam into the housings ByPass throat;
but grinding the lower disc diameter ~0m001 slightly smaller makes it work & allows a longer TStat stroke + larger flow opening to the radiator!
D

 

[Otis413]

Another update:
Concerning the sensor holes being bigger in the alum housing I bought, I ordered a few different size o-rings from Amazon and found the "8 mm ID, 14 mm OD, 3 mm" (3x8mm or 0.118 x 0.315 In.) viton o-rings fit with some wiggling and using the OEM clips (the clips that came with the housing were smaller gauge and not as strong), rated for 350*F.

 

[DILLARD000]

^ Good info.