How to fix transmission fluid leak Audi A6

Fixing Transmission Fluid Leak on Audi A6 C7 (2011-2018)

Step 1: Identify Leak Location

1. Visual Inspection:

   • Safely lift the vehicle using a hydraulic jack and support with jack stands.
   • Inspect around the transmission pan, fluid lines, and seals for signs of leakage.
   • Check the fluid color and smell; burnt or dark fluid indicates internal issues.

2. Use UV Dye:

   • Add a UV dye to the transmission fluid and run the engine.
   • Use a UV light to trace the leak source accurately.

3. Inspect Transmission Pan Gasket:

   • Check for leaks around the transmission pan gasket, a common leak point.

4. Check Transmission Fluid Lines:

   • Examine the fluid lines for any cracks or loose connections.

5. Inspect Seals:

   • Pay attention to the input and output shaft seals as potential leak sources.

Tools Required

• Hydraulic jack and jack stands
• Socket set and wrench
• Transmission fluid (specific to Audi A6 specifications)
• UV dye and UV light
• Torque wrench
• Replacement gasket or seal kit
• Drain pan
• Screwdriver set

Repair Instructions

Step 1: Replace Transmission Pan Gasket

1. Drain Transmission Fluid:

   • Place a drain pan under the transmission pan.
   • Remove the drain plug and allow fluid to drain completely.

2. Remove Transmission Pan:

   • Unscrew all bolts securing the transmission pan.
   • Carefully remove the pan and clean any old gasket material from the pan and transmission body.

3. Install New Gasket:

   • Place the new gasket on the transmission pan.
   • Reinstall the pan and torque the bolts to the manufacturer’s specifications.

Step 2: Replace Fluid Lines

1. Disconnect Old Lines:
   • Use a wrench to disconnect the old transmission fluid lines.
   • Replace with new lines and ensure all connections are tight.

Step 3: Replace Seals

1. Replace Input/Output Shaft Seals:
   • If leaking seals are identified, remove the respective components to access the seals.
   • Carefully remove the old seal without damaging the housing.
   • Press in the new seal and reassemble the components.

Step 4: Refill and Test

1. Refill Transmission Fluid:

   • Use a funnel to refill the transmission with the correct type and amount of fluid.
   • Start the vehicle and let it idle; shift through all gears to circulate the fluid.

2. Check for Leaks:

   • Inspect for any signs of leaks after the repair.
   • Ensure fluid levels are correct after running the vehicle.

Final Steps

• Road Test: Conduct a road test to ensure proper transmission operation.
• Monitor Fluid Levels: Check fluid levels and for leaks over the next few days.

Important Notes

• Always use the manufacturer-recommended transmission fluid type.
• Torque specifications are crucial for preventing new leaks; refer to the vehicle’s service manual.
• If the problem persists or the leak source is internal, consult a professional technician.