This procedure covers the removal and replacement of the transmission oil cooler on a 2016-2024 Hyundai Tucson with the 2.5L I4 engine and AWD transmission.

Warnings

Tools required

Parts

• Transmission oil cooler assembly × 1 — Use OEM specification
• Transmission cooler line O-rings × 4 — Use OEM specification
• Transmission drain plug crush washer × 1 — Use OEM specification
• Hyundai SP-IV-M ATF × 4 — Use OEM specification

Fluids

• Hyundai SP-IV-M ATF — 4 qt

Preparation

1. Park vehicle on level ground and apply parking brake
2. Allow engine and transmission to cool completely (minimum 2 hours after operation)
3. Disconnect negative battery cable
4. Raise and safely support vehicle on jack stands at manufacturer lift points
5. Remove front engine splash shield and undertray fasteners
6. Place large drain pan beneath transmission oil cooler area
7. Have approximately 12 quarts of drain capacity available for combined ATF and coolant

Procedure

1. 1

   Drain transmission fluid
   Locate the transmission drain plug on the bottom of the transmission pan. Position drain pan beneath plug. Remove drain plug and allow fluid to drain completely. Inspect drain plug and replace crush washer.
   ⚠Initial fluid flow will be rapid. Ensure drain pan is properly positioned.
   Torque spec

   Transmission Drain Plug30 Nm (22 lb-ft)
2. 2

   Drain coolant from radiator
   Place drain pan beneath radiator drain valve. Open radiator drain valve or remove lower radiator hose to drain coolant until level is below the transmission oil cooler connections. Close drain valve when complete.
   ⚠️Coolant is toxic to animals and children. Contain all spillage and dispose of according to local regulations.
3. 3

   Disconnect transmission cooler lines
   Locate the transmission cooler inlet and outlet lines at the oil cooler. Using the appropriate transmission line disconnect tool, release the quick-connect fittings. Have shop rags ready to catch residual fluid. Cap or plug open lines immediately to prevent contamination.
   ⚠Lines may still contain pressurized fluid. Release pressure slowly and have rags positioned to catch spillage.
4. 4

   Remove cooler mounting hardware
   Remove the transmission oil cooler mounting bolts securing the cooler to its bracket or radiator assembly. Support the cooler as you remove the final bolt to prevent it from falling. Note the orientation and position of any brackets or spacers for reassembly.
   Torque spec

   Mounting Bolts61 Nm (45 lb-ft)
5. 5

   Remove transmission oil cooler
   Carefully maneuver the transmission oil cooler out of the engine bay. Tilt and rotate as needed to clear hoses, wiring, and structural components. Drain any remaining fluid into the drain pan.
6. 6

   Inspect cooler lines and fittings
   Examine transmission cooler lines for cracks, abrasion, or deterioration. Check quick-connect fittings for damage. Clean all mating surfaces on the transmission lines and mounting points using a wire brush. Remove any debris or old gasket material.
7. 7

   Install new O-rings on cooler fittings
   Remove old O-rings from the transmission cooler line fittings. Lubricate new O-rings with clean ATF and install them onto the new transmission oil cooler inlet and outlet ports. Ensure O-rings are properly seated in their grooves.
   ℹ️Do not use petroleum-based lubricants on O-rings. Use only clean ATF for lubrication.
8. 8

   Position new transmission oil cooler
   Carefully maneuver the new transmission oil cooler into position, reversing the removal path. Align mounting holes with brackets. Ensure no wiring or hoses are pinched during installation.
9. 9

   Install cooler mounting bolts
   Install all transmission oil cooler mounting bolts hand-tight first to ensure proper alignment. Torque mounting bolts to specification in a criss-cross pattern to ensure even seating. Verify cooler is secure and properly aligned.
   Torque spec

   Mounting Bolts61 Nm (45 lb-ft)
10. 10

    Reconnect transmission cooler lines
    Connect the transmission cooler inlet and outlet lines to the new cooler. Push quick-connect fittings firmly until they click into place. Tug gently on each line to verify secure connection. Ensure no cross-threading or misalignment.
11. 11

    Reinstall transmission drain plug
    Install new crush washer on transmission drain plug. Thread drain plug into transmission pan by hand to avoid cross-threading, then torque to specification.
    Torque spec

    Transmission Drain Plug30 Nm (22 lb-ft)
12. 12

    Refill transmission fluid
    Through the transmission dipstick tube or fill port, add approximately 3.5-4.0 quarts of Hyundai SP-IV-M ATF. Do not overfill at this stage. Start engine and allow to idle while monitoring for leaks at cooler connections.
    ⚠Use only Hyundai SP-IV-M ATF. Other fluids may cause transmission damage and void warranty.
13. 13

    Refill coolant system
    Refill radiator with Hyundai/Kia Long Life Coolant (Green) to proper level. Burp cooling system according to manufacturer procedure to remove air pockets. Check overflow reservoir and fill to appropriate mark.

Reassembly

1. Reinstall front engine splash shield and undertray, ensuring all fasteners are secure
2. Lower vehicle from jack stands
3. Reconnect negative battery cable
4. Start engine and cycle transmission through all gears with brake applied
5. Check transmission fluid level with engine at operating temperature and verify proper level on dipstick
6. Add additional ATF if needed to reach proper level (total capacity approximately 10 quarts, but only replace what was drained)
7. Inspect all connections for leaks while engine is running

Verification

• Test drive vehicle for 10-15 minutes, ensuring smooth shifting in all gears
• Return to level ground and recheck transmission fluid level with engine running and at operating temperature
• Inspect transmission oil cooler connections and mounting area for any signs of fluid leakage
• Check coolant level in overflow reservoir and top off if needed
• Verify no warning lights are illuminated on instrument cluster
• Monitor transmission temperature gauge (if equipped) to ensure it remains in normal operating range

More procedures for this vehicle