Changing the transmission fluid in your Audi with a manual gearbox is crucial for maintaining its performance and longevity. While Audi claims the factory fill is “lifetime,” regular fluid changes can significantly extend the life of your transmission. This guide provides a step-by-step walkthrough of the process, using Redline MT-90 75W/90 synthetic fluid as an example.
Preparing for the Fluid Change
Before you begin, ensure your Audi is securely positioned on four jack stands, leveled to ensure proper filling. You’ll need approximately 4.5 quarts of gear oil, new subframe bolts (if replacing), a variety of tools including Torx and Allen keys, screwdrivers, and sockets, and a fluid pump or syringe.
Accessing the Transmission
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Undertrays: Remove the front and rear undertrays using the appropriate tools. This will expose the transmission and surrounding components. Inspect for any damage, like a missing sway bar bracket.
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Power Steering Cooler: Disconnect the nut securing the power steering cooler to the front subframe using a 10mm socket.
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Front Subframe: Remove the six bolts holding the front subframe with an 18mm socket. Note: Subframe appearance may vary depending on modifications. Replace these bolts with new ones.
Draining and Filling the Fluid
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Locating Plugs: Identify the fill (red) and drain (blue) plugs on the transmission.
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Draining: Using a 10mm Allen key, remove the fill plug first, then the drain plug. Let the old fluid drain completely into a pan. Inspect the drained fluid for debris.
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Replacing Drain Plug: Once drained, reinstall the drain plug, torquing it to approximately 32 ft-lbs. Note: This Audi model may not use crush washers.
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Filling: Using a fluid pump or syringe, pump new gear oil into the fill hole until it begins to overflow. This indicates the transmission is full. It should take approximately 4.5 quarts.
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Replacing Fill Plug: Reinstall the fill plug, torquing it to approximately 32 ft-lbs.
Reassembly and Final Steps
Reinstall the front subframe with new bolts, torquing to 90 ft-lbs and then applying an additional 135 degrees of rotation. Reconnect the power steering cooler, reinstall the undertrays, and lower the vehicle. Clean any spilled fluid with brake cleaner.
Fluid Comparison and Maintenance Intervals
Regular fluid changes are key to a healthy manual transmission. The difference between fresh and used fluid can be significant, affecting shifting smoothness.
Changing your Audi Manual Transmission fluid every 30,000 miles, regardless of manufacturer recommendations, will contribute to its long-term reliability and performance. You’ll notice improved shifting and overall drivability. Don’t forget to inspect for debris in the old fluid as it can indicate potential problems.
