Coolant Reservoir

This procedure covers the removal and replacement of the coolant reservoir on a 2015-2020 Ford F-150 with the 3.5L EcoBoost V6 engine, including coolant draining and refilling.

Warnings

Tools required

Parts

• Coolant reservoir × 1 — Use OEM Ford replacement
• Coolant reservoir cap × 1 — Replace if damaged or doesn't hold pressure
• Hose clamps × 2 — Replace if corroded

Fluids

• Motorcraft Orange Coolant — 2 qt

Preparation

1. Ensure engine is completely cold to the touch
2. Park vehicle on level ground and engage parking brake
3. Open hood and secure with prop rod
4. Place drain pan under the radiator drain petcock area
5. Locate the coolant reservoir on the passenger side of the engine bay near the firewall

Procedure

1. 1

   Drain coolant from system
   Slowly turn the reservoir cap counterclockwise to release any residual pressure, then remove completely. Locate the radiator drain petcock at the bottom of the radiator on the driver side. Turn the petcock counterclockwise to open and allow coolant to drain into the pan. You only need to drain enough to lower the level below the reservoir, not the entire system.
   Torque spec

   Drain Petcock8 Nm (6 lb-ft)
2. 2

   Disconnect overflow hose
   Locate the small overflow hose connected to the top or side of the reservoir. Use hose clamp pliers or a flathead screwdriver to compress or loosen the spring clamp, then slide it back along the hose. Pull the hose straight off the reservoir nipple. Position a shop towel underneath to catch residual coolant.
3. 3

   Disconnect main supply hose
   Locate the larger coolant supply hose at the bottom of the reservoir. Loosen the hose clamp by compressing the spring-type clamp or loosening the screw-type clamp. Twist the hose gently while pulling to remove it from the reservoir. Be prepared for coolant to drain from the hose; direct it into the drain pan.
4. 4

   Remove reservoir mounting bolts
   Using a 10mm socket, remove the two mounting bolts securing the reservoir to the bracket on the inner fender. On 2015-2020 models, one bolt is at the top and one at the bottom of the mounting bracket. Support the reservoir while removing the second bolt.
   Torque spec

   Reservoir Mounting Bolts8 Nm (6 lb-ft)
5. 5

   Remove reservoir
   Lift the coolant reservoir straight up and out of the engine bay. Tilt it as needed to maneuver around nearby components. Inspect the mounting bracket for damage or corrosion. Pour any remaining coolant from the reservoir into the drain pan.
6. 6

   Prepare new reservoir
   Inspect the new reservoir for cracks or damage. Transfer the reservoir cap to the new reservoir if reusing (verify it holds pressure properly). Check that all hose connections are clean and free of debris. Compare the new reservoir to the old one to confirm correct replacement part.
7. 7

   Install new reservoir
   Position the new reservoir into the mounting bracket, aligning the bolt holes. Thread both mounting bolts by hand first to ensure proper alignment, then tighten to specification using a 10mm socket. Torque to 8.0 Nm (6.0 lb-ft) if using a torque wrench, or snug by hand plus 1/4 turn.
   Torque spec

   Reservoir Mounting Bolts8 Nm (6 lb-ft)
8. 8

   Reconnect main supply hose
   Push the main coolant supply hose firmly onto the bottom nipple of the new reservoir until it is fully seated. Position the hose clamp approximately 1/4 inch from the end of the hose and tighten to 5.0 Nm (3.0 lb-ft). Ensure the hose is routed properly without kinks.
   Torque spec

   Hose Clamps5 Nm (3 lb-ft)
9. 9

   Reconnect overflow hose
   Push the overflow hose onto the reservoir nipple until fully seated. Slide the spring clamp into position over the connection point, approximately 1/4 inch from the end of the hose. If using a screw-type clamp, tighten to 5.0 Nm (3.0 lb-ft).
   Torque spec

   Hose Clamps5 Nm (3 lb-ft)
10. 10

    Close drain petcock and refill coolant
    Close the radiator drain petcock by turning it clockwise until hand tight (8.0 Nm / 6.0 lb-ft). Using a funnel, pour Motorcraft Orange Coolant into the reservoir until it reaches the COLD FILL MAX line. Do not overfill. Install the reservoir cap by turning clockwise until it clicks.
    Torque spec

    Drain Petcock8 Nm (6 lb-ft)
11. 11

    Burp cooling system and check level
    Start the engine and let it idle with the heater on maximum temperature and fan speed. Allow the engine to reach normal operating temperature (approximately 10 minutes). Watch the temperature gauge to ensure it stays in the normal range. Shut off the engine and allow to cool for 30 minutes. Recheck the coolant level in the reservoir and top off to the COLD FILL MAX line if needed.

Reassembly

1. Verify all hose clamps are properly tightened and positioned
2. Ensure reservoir cap is installed and sealing properly
3. Wipe down any coolant residue from engine bay components
4. Double-check that drain petcock is fully closed

Verification

• Check coolant level in reservoir with engine cold - should be at COLD FILL MAX line
• Inspect all hose connections for leaks while engine is running at operating temperature
• Verify no coolant drips or puddles under vehicle after test drive
• Confirm heater produces hot air at idle and while driving
• Monitor temperature gauge during first few drives to ensure it remains in normal range
• Recheck coolant level after 24 hours and top off if necessary

Related trouble codes on this vehicle

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