Transfer Case Fluid Change

This procedure drains and refills the transfer case fluid on 2016-2024 Hyundai Tucson AWD models with the 2.5L I4 engine, requiring removal of the front driveshaft to access the fill plug.

Warnings

Tools required

Parts

• Transfer case drain plug washer × 1 — Use OEM specification
• Transfer case fill plug washer × 1 — Use OEM specification

Fluids

• Transfer Case Fluid — 2.5 qt

Preparation

1. Park vehicle on level surface and engage parking brake
2. Place wheel chocks behind rear wheels
3. Allow transfer case to cool if vehicle was recently operated
4. Raise front of vehicle and support on jack stands at manufacturer lift points
5. Remove front wheels to improve access to driveshaft connection points
6. Locate transfer case drain plug on bottom of transfer case housing and fill plug on front face (behind front driveshaft)

Procedure

1. 1

   Mark driveshaft orientation
   Before removing the front driveshaft, use a paint marker or scribe to mark the relationship between the front driveshaft CV flange and the transfer case output flange. This ensures proper reinstallation alignment and prevents driveline vibration.
2. 2

   Remove front driveshaft CV bolts
   Remove the six CV bolts connecting the front driveshaft to the transfer case output flange. Use a 13mm socket and hold the driveshaft to prevent rotation. Keep bolts organized for reinstallation.
3. 3

   Support and remove front driveshaft
   Support the front driveshaft with one hand or a bungee cord. Carefully pull the driveshaft away from the transfer case output flange and secure it to the side using mechanics wire or zip ties to prevent damage. Do not let it hang unsupported as this can damage the front differential CV joint.
4. 4

   Clean drain plug area
   Use a wire brush to clean the area around the transfer case drain plug on the bottom of the transfer case housing. Remove any dirt, debris, or road grime to prevent contamination when the plug is removed.
5. 5

   Position drain pan and remove drain plug
   Position the drain pan directly under the drain plug. Using a 14mm socket, carefully loosen and remove the drain plug. Allow fluid to drain completely into the pan. Inspect the drained fluid for metal particles or debris which may indicate internal wear.
   ⚠Fluid may still be warm. Wear gloves to prevent skin contact.
   Torque spec

   Transfer Case Drain Plug25 Nm (18 lb-ft)
6. 6

   Inspect and replace drain plug washer
   Once fluid has completely drained, inspect the drain plug and washer. The aluminum or copper crush washer should be replaced with a new one. Clean the drain plug threads with a shop rag and verify the magnetic tip (if equipped) is free of excessive metal debris.
7. 7

   Reinstall drain plug
   Install the new washer on the drain plug. Thread the drain plug into the transfer case by hand to avoid cross-threading, then tighten to specification using a torque wrench.
   Torque spec

   Transfer Case Drain Plug25 Nm (18 lb-ft)
8. 8

   Locate and clean fill plug
   With the front driveshaft removed, you now have clear access to the fill plug on the front face of the transfer case housing. Clean the area around the fill plug with a wire brush to prevent contamination.
9. 9

   Remove fill plug
   Using a 14mm socket, carefully remove the fill plug. Inspect the fill plug washer and replace if damaged or compressed. Keep the fill plug readily accessible as you will need to reinstall it once filling is complete.
   Torque spec

   Transfer Case Fill Plug25 Nm (18 lb-ft)
10. 10

    Fill transfer case with fluid
    Using a fluid transfer pump with attached hose, insert the hose into the fill plug opening. Pump 2.5 quarts of the specified transfer case fluid into the housing. Fill slowly to prevent air pockets and allow fluid to settle. Fluid is at correct level when it begins to drip from the fill hole.
    ⚠️Vehicle MUST be level during this step. Filling on an incline will result in improper fluid level.
11. 11

    Reinstall fill plug
    Once fluid level is correct (dripping from fill hole), install a new washer on the fill plug. Thread the fill plug in by hand, then tighten to specification using a torque wrench. Wipe away any spilled fluid from the transfer case housing.
    Torque spec

    Transfer Case Fill Plug25 Nm (18 lb-ft)
12. 12

    Reinstall front driveshaft
    Remove the securing wire or zip ties from the front driveshaft. Align the marks made during disassembly and carefully guide the CV joint back onto the transfer case output flange. Ensure proper alignment before installing bolts.
    ℹ️Driveshaft must be installed in original orientation to prevent vibration issues.
13. 13

    Install and torque CV bolts
    Install all six CV bolts finger-tight first to ensure proper alignment. Then tighten in a star pattern to specification using a torque wrench. Double-check that all bolts are fully torqued.
14. 14

    Reinstall wheels and lower vehicle
    Reinstall the front wheels and tighten lug nuts in a star pattern to specification. Carefully lower the vehicle from the jack stands and perform final torque check on lug nuts with vehicle on ground.
    Torque spec

    Wheel Lug Nuts140 Nm (103 lb-ft)

Reassembly

1. Verify all drain and fill plugs are torqued to specification
2. Confirm front driveshaft CV bolts are properly torqued and secured
3. Check undercarriage for any fluid leaks or drips
4. Verify no tools or materials were left in the work area
5. Dispose of used transfer case fluid according to local environmental regulations

Verification

• Start the engine and allow it to idle for 2-3 minutes
• With engine running, shift transmission through all gear positions including D, N, R, and back to P
• Turn off engine and recheck transfer case fill plug area for leaks
• Test drive vehicle at low speeds in a safe area, verifying smooth AWD operation with no vibrations or unusual noises
• After test drive, raise vehicle and perform final leak inspection at both drain and fill plugs
• Check that no fluid is leaking from driveshaft CV connection points

Related trouble codes on this vehicle

Codes that commonly send this job to the bay — tap one for symptoms, causes, and diagnostic steps.

Chasing one of these codes and not sure which part is guilty? Ask a master mechanic about YOUR car →

More procedures for this vehicle