Tools You'll Need:
* Jack and jack stands: Essential for safe vehicle support. Never work under a vehicle supported only by a jack.
* Wheel chocks: To secure the vehicle while it's jacked up.
* Wrench(es): You'll need the correct size to remove the drain and fill plugs. Sizes vary depending on the Explorer's configuration, so check your owner's manual. Often a 10mm and possibly an 8mm or 11mm will be needed.
* Drain pan: To catch the old fluid.
* Funnel: To pour in the new fluid.
* Torque wrench: Highly recommended to tighten the drain and fill plugs to the correct specification (again, check your owner's manual). Over-tightening can strip the threads.
* Gloves: To protect your hands from the dirty fluid.
* Shop rags or paper towels: For cleanup.
* New rear differential fluid: The correct type and quantity (check your owner's manual). This is usually 75W-140 or 75W-90 gear oil, often synthetic.
Procedure:
1. Safety First: Park your Explorer on a level surface, engage the parking brake firmly, and use wheel chocks to prevent movement.
2. Jack Up the Vehicle: Carefully jack up the rear of the Explorer and securely support it with jack stands.
3. Locate the Differential: The rear differential is located in the rear axle housing, usually near the center of the rear of the vehicle.
4. Locate Drain Plug: The drain plug is usually located at the bottom of the differential housing. It might have a magnetic tip to catch metal particles.
5. Remove Drain Plug: Position your drain pan under the drain plug and carefully loosen and remove the drain plug using the appropriate wrench. Let the old fluid drain completely. This can take some time.
6. Locate Fill Plug: The fill plug is usually located on the top or side of the differential housing.
7. Remove Fill Plug (Optional but Recommended): It's helpful to remove the fill plug *before* draining to verify that you can remove it and to get a better sense of the fluid level. If it's extremely difficult to remove, get assistance from a mechanic.
8. Replace Drain Plug: Once the old fluid has drained, reinstall the drain plug and tighten it to the correct torque specification using your torque wrench. Don't overtighten!
9. Add New Fluid: Using a funnel, carefully pour the new rear differential fluid into the fill plug opening until it begins to overflow slightly. The level should be even with the fill hole. Consult your owner's manual for the correct amount of fluid required.
10. Replace Fill Plug: Reinstall the fill plug and tighten it to the correct torque specification.
11. Lower Vehicle: Carefully lower your Explorer using the jack.
12. Check for Leaks: Inspect the area around the drain and fill plugs for any leaks.
13. Dispose of Old Fluid: Properly dispose of the used differential fluid according to local regulations. Many auto parts stores will accept used oil.
Important Considerations:
* Fluid Type: Using the incorrect fluid can severely damage your rear differential. Always consult your owner's manual.
* Torque Specifications: Over-tightening the plugs can strip the threads. Use a torque wrench and follow the specifications in your owner's manual.
* Accessibility: The location and accessibility of the drain and fill plugs can vary depending on the specific model of your 2004 Ford Explorer. If you're unsure, consult a repair manual specific to your vehicle.
* If Unsure, Seek Professional Help: If you are not comfortable performing this task, it's best to take your Explorer to a qualified mechanic.
This guide provides general information. Always consult your owner's manual for specific instructions and torque specifications for your vehicle. Improperly performing this task can lead to damage to your vehicle.
