Thermostat with Housing Assembly - 1AEMX00209

Warranty & Shipping
How-To & Tools
Product Reviews
Vehicle Fit

If your vehicle is leaking coolant around the thermostat housing, or the outlet is broken or cracked, then this could be your solution.


  • Thermostat & Housing Assembly
  • Replaces dealer part numbers: 2L2Z-8592-BA, 2L2Z-8592-BB, 2L2Z8592BA, 2L2Z8592BB
  • Direct replacement
  • Built to strict quality control standards
  • Plastic construction
  • Thermostat is included

Over time the mating surfaces on the housing can crack. If you are experiencing these issues replace your housing with our direct replacement!

Item Condition: New

Attention California Customers:

WARNING: Cancer and Reproductive Harm -

Lifetime Warranty

This item is backed by a Limited Lifetime Warranty. In the event this item should fail due to manufacturing defects during intended use, we will exchange the part free of charge (excludes shipping charges) for the original purchaser.

  1. step : Draining the Coolant (1:00)
    • Remove the radiator cap by turning counterclockwise
    • Remove the four 10mm bolts securing the cover underneath the radiator
    • Pull the cover down
    • Have a drain pan ready
    • Open up the plug with a 19mm wrench
    • Let the radiator drain
    • Hand-tighten the plug
  2. step : Removing the Intake Tube (2:39)
    • Remove the Phillips head screws from the throttle body cover
    • Remove the 7mm bolt from the throttle body cover
    • Remove the breather hose from the intake hose
    • Remove the intake hose
  3. step : Removing the Upper Radiator Hose (3:38)
    • Remove the 13mm alternator bolt
    • Move the wiring harness
    • Have a drain pan ready
    • Compress and slide the hose clamp nearest the radiator back
    • Twist off the radiator hose off of the radiator
    • Let the hose drain
    • Compress and slide the second hose clamp back
    • Remove the radiator hose from the water pump
  4. step : Removing the Thermostat (4:41)
    • Remove the three 8mm bolts from the thermostat cover
    • Remove the cover
    • Remove the thermostat
  5. step : Removing the Coolant Temperature Sensor (5:29)
    • Remove the lock clip with a pair of pliers
    • Pry the sensor up with a flat blade screwdriver
    • Disconnect the wiring harness
  6. step : Installing the Coolant Temperature Sensor (7:01)
    • Insert the sensor into place
    • Connect the sensor wiring harness
    • Insert the lock clip to the sensor
  7. step : Installing the Thermostat (7:40)
    • Insert the thermostat into place
    • Press on the cover
    • Tighten the three 8mm bolts to the cover
  8. step : Installing the Upper Radiator Hose (8:36)
    • Tighten the 13mm bolt to the wiring harness bracket on the alternator
    • Connect the radiator hose to the water pump
    • Tighten the clamp to the hose
    • Connect the radiator hose to the radiator
    • Tighten the clamp to the hose
  9. step : Reinstalling the Intake Tube (9:44)
    • Insert the intake tube to the air box and throttle body
    • Tighten the hose clamps with a flat blade screwdriver
    • Reconnect the breather hose
  10. step : Bleeding the System (10:52)
    • Fill the radiator with the appropriate mixture
    • Leave the radiator cap off
    • Leave the funnel in the radiator
    • Place a drain pan beneath the radiator
    • Put the fan on the lowest setting
    • Put the heat on the highest setting
    • Run the vehicle
    • Watch the air bubbles
    • Refill coolant as needed while the vehicle is running
    • Let the coolant reach operating temperature
    • Wait for the coolant level to stop dropping
    • Check for heat to come out of the vents
    • Turn the vehicle off
    • Reinstall the radiator cap
    • Top off the overflow bottle if necessary
    • Test drive the vehicle and monitor the coolant levels

Tools needed for replacement:

    Diagnostic Tools

  • Anti-Freeze Hydrometer

  • General Tools

  • Drain Pan
  • Funnel

  • Pliers, Cutters & misc Wrenches

  • Needle nose pliers

  • Ratchets & Related

  • Swivel
  • Ratchet
  • Torque Wrench
  • Socket Extensions

  • Screwdrivers & Related

  • Phillips Head Screwdriver
  • Flat Blade Screwdriver

  • Sockets - Metric

  • 13mm Socket
  • 7mm Socket

  • Wrenches - Metric

  • 19mm Wrench

5.00/ 5.0
14 reviews
5 Stars
4 Stars
3 Stars
2 Stars
1 Star
Thermostat housing
The shipping was fast the product was as described
October 11, 2017
It was so great to find the part I needed and the price was incredible. Everywhere else I shopped the price for the thermostat housing was close to $80 and it didnt include the sensor! My husband installed it and the issue was resolved! I would highly recommend people to search your website cause your products are high quality and the prices incredible!
January 27, 2018
Highly recommend
I needed a new thermostat housing for my 02 explorer so I called my local auto parts store just to find out it was 85 dollars and I had to wait 3-5 days since it was a special order. Looked online came across a1auto and found it for a fraction of the price even with the 2 day delivery I still spent less than what I would have if I would have gone thru my local auto parts store
February 12, 2018
Part working well
Just changed it out today. Working well. Great price. I should have changed the temperature sensor o- ring when I had it out; but did it later. Live and learn. Still have a small drop on the floor but I think it’s from fluid caught in the frame.
February 24, 2018
Worked perfectly
Old one had a crack in it. This one fit perfectly and no more leak. Received quickly. Will be ordering again from 1A Auto.
February 26, 2018
Great part great price perfect fit great shipping overall easy to install great seller!!!
March 31, 2018
grate price
Shipped on time, grate quality, nice price fit great best in town will buy from them again
April 14, 2018
Thermostat housing
The housing arrived in 2 days and performed well after installation
April 18, 2018
Perfect fit
Shipping was on time and parts came ready to install. Was very easy to install and fit perfectly. Have started buying my parts here all the time as you can’t beat the price and quality. Thanks!
May 2, 2018
Great Part from and Excellent Vendor
This water jacket thermo housing fit as described. Took less than an hour while working with my son on his first time changing such a part. 1A Auto supplied the right part the first time as always.
May 8, 2018
Ford Exploder thermo
Thermostat fit perfectly, good price. Video of install on YouTube is very helpful...going to see if Mike will come to my garage to help with the next tough job!!
July 20, 2018
Thermostat housing
Product came fast and it was perfect for my vehicle. Had no problem whatsoever once I installed it. I’ll keep buying more product from
July 21, 2018
Best in the business!
Parts from 1AAuto at of great quality and at the best price around. My new go to one stop shop!
November 22, 2018
The part came in a timely fashion it was a perfect fit no problems I recommend everybody to use this site to order parts it saves you a lot of money plus you guys have videos we could do it yourself good job thanks again
November 28, 2018
Will this fit my car? Add a vehicle to make sure
Customer Q&A
Ask a question to 1A Auto customers who purchased the product
Is there a gasket required for the lower housing to the manifold?
Robert S January 14, 2016
Comes with an O ring, if memory serves me right
Johnny M January 14, 2016
No. This part comes complete with an O-ring that replaces any gasket and does not need any sealant. Just make sure the O-ring is in place and all surfaces are clean.
John H January 14, 2016
German T January 14, 2016
Hi, The answer its yes. The item came withe a Oring not really a gasket. In my case the unit works perfect.
Rafael M January 15, 2016
This will come with an O-ring that you need to install the housing. This will also come with a lifetime warranty. Thank you and have a great day!
Derek C January 19, 2016
Ronald F October 12, 2017
the thermomstat housing i replaced on my 07 4 litre is new my question is two ports on top, one for the heat senser the other one is open, can i plug the hole up, or leave as is ?thanks for your answer
Wendell C December 14, 2017
Thanks for your question! All of the ports on the housing should have matched up with a line or plug on the factory part mounted in the vehicle. Check the images that we have on our site to ensure it matches the part you received from us. Please contact us with any other questions. Thank you!
Adam G December 14, 2017
The other hole is vital and is the one where the ECT or engine managment Coolant sensor is installed,that particular sensor sends information to the Control module for the purpose of enriching or leaning the fuel mixture by controling the opening of the fuel injectors.
R O October 9, 2018
Does the sensor come with it?
Chuck S May 8, 2018
Have to use the original sensor and a new seal.
Lance H May 8, 2018
normally it dosen’t , only the o-ring & clip. it always comes this way even if you get it from ford. make sure to turn sensor after install to let o-ring seat properly
Jaime G May 8, 2018
Year Make Model Description
2002-2010Ford Explorer Ford Explorer Upper & Lower Thermostat with Housing Assembly V6 4.0L
2007-2010Ford Explorer Sport Trac Ford Explorer Sport Trac Upper & Lower Thermostat with Housing Assembly V6 4.0L
2002-2010Mercury Mountaineer Mercury Mountaineer Upper & Lower Thermostat with Housing Assembly V6 4.0L
Part #: 1AEMX00209

Order must be placed by 4pm ET

Get it in: 2 - 4 Business Days

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How-to Video:

(14:01 min)