Kia Sorento Third Generation (2015-2020) Transmission Fluid Leak Repair

Symptoms

• Transmission Fluid Puddles: Noticeable red or brown fluid spots under the vehicle where it is parked.
• Low Transmission Fluid Levels: Warning light or dipstick reading showing low fluid levels.
• Slipping Gears: Difficulty shifting or delay in gear engagement.
• Unusual Noises: Grinding or whining sounds when the vehicle is in gear.

Diagnostic Steps

1. Visual Inspection:

   • Check the transmission fluid level using the dipstick.
   • Inspect the ground under the vehicle for transmission fluid leaks.
   • Look for signs of fluid around transmission seals, gaskets, and pan.

2. Identify the Leak Source:

   • Clean the transmission casing with a degreaser to remove old fluid and dirt.
   • Use a flashlight to inspect the transmission pan, seals, and hoses for cracks or damage.
   • Pay close attention to the input/output shaft seals and the transmission pan gasket.

3. Perform a Pressure Test (if necessary):

   • Use a pressure gauge to check for leaks while the vehicle is running (only if you have the proper training and equipment).

Tools Required

• Socket set (including ratchet and extensions)
• Torque wrench
• Screwdrivers (flathead and Phillips)
• Transmission fluid (specific to Kia Sorento)
• Transmission sealant (if applicable)
• Oil catch pan
• Clean rags
• Brake cleaner or degreaser
• Flashlight
• Safety goggles and gloves

Repair Instructions

Step 1: Preparing the Vehicle

1. Safety First: Park the vehicle on a flat surface, engage the parking brake, and wear safety goggles and gloves.
2. Raise the Vehicle: Use a hydraulic jack to lift the front of the vehicle and secure it with jack stands.

Step 2: Draining the Transmission Fluid

1. Locate the Drain Plug: Find the transmission drain plug on the transmission pan.
2. Remove the Drain Plug: Place an oil catch pan underneath and remove the drain plug to drain the fluid completely.
3. Inspect the Fluid: Check the fluid for metal shavings or burning smell, which may indicate internal damage.

Step 3: Inspecting and Replacing Gaskets/Seals

1. Remove the Transmission Pan:

   • Unbolt the transmission pan using the socket set. Be mindful of the order and position of the bolts for reinstallation.
   • Gently pry the pan off to avoid damaging it. If necessary, tap it lightly with a rubber mallet.

2. Remove Old Gasket:

   • Scrape off the old gasket material from both the pan and the transmission surface. Ensure the surface is clean and free of debris.

3. Inspect Seals:

   • Check the input and output shaft seals for wear and damage. Replace if necessary.
   • If the seals are damaged, you will need to remove the driveshaft or axles to access them.

Step 4: Reinstalling the Transmission Pan

1. Apply New Gasket:

   • Place a new gasket on the transmission. If using sealant, apply a thin layer according to the manufacturer’s recommendations.

2. Reinstall the Transmission Pan:

   • Position the transmission pan back and align it with the bolt holes.
   • Hand-tighten the bolts before using the torque wrench to tighten them to the manufacturer’s specifications (usually around 8-12 ft-lbs, but verify with the repair manual).

Step 5: Refilling Transmission Fluid

1. Replace Drain Plug: After ensuring no leaks from the pan, reinstall the drain plug securely.
2. Refill Transmission Fluid:
   • Use a funnel to pour the new transmission fluid into the dipstick tube. Refer to the owner’s manual for the proper fluid type and amount (usually around 6-9 quarts, depending on the service performed).
3. Check Fluid Level: Start the engine and let it warm up. Shift through all gears, then check the fluid level with the dipstick, adding more fluid as necessary.

Step 6: Final Inspection

1. Check for Leaks: After refilling, inspect the pan and seals for any signs of leaking fluid.
2. Test Drive: Take the vehicle for a short drive to ensure proper operation of the transmission and monitor for leaks.

Step 7: Clean Up

• Dispose of old transmission fluid and materials according to local regulations.
• Lower the vehicle safely and remove jack stands.

Conclusion

Repairing a transmission fluid leak in a Kia Sorento involves a systematic approach to diagnose the source of the leak, replace damaged seals or gaskets, and refill the transmission fluid. Following these steps carefully will help ensure that the repair is successful and that the vehicle operates smoothly. If the problem persists or if you are unsure about any steps, consult a professional mechanic for assistance.