Anyone has change the Transmission oil on a HS PHEV year 2021 by yourselves and can share steps, number of liters used and brand of the oil please?

[twido]

Anyone has change the Transmission oil on a HS PHEV year 2021 by yourselves and can share steps, number of liters used and brand of the oil please?

 

[Technonotice]

You've got to love Google Gemini:

Gemini said​

Changing the transmission fluid on a 2021 MG HS PHEV is a specific maintenance task because the vehicle uses a 10-speed EDU (Electronic Drive Unit) transmission that pairs a 6-speed automatic with a 4-speed electric drive motor.

Here is the breakdown of the requirements and the procedure.

Quick Specs​

• Oil Type: DEXRON® DCT Fluid (Dual Clutch Transmission Fluid).
• Capacity: Approximately 2.45 Liters.
• Recommended Brand: Castrol Transmax DCT (specifically "Castrol BOT 351LV" is often cited in MG service kits) or any high-quality fully synthetic DCT fluid meeting the Dexron DCT specification.
• Interval: Every 45,000 miles (72,000 km) or 3 years, whichever comes first.

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Step-by-Step Procedure​

Note: Because this is a Plug-in Hybrid (PHEV), ensure the vehicle is in "Ready" mode off and the high-voltage system is not active. Some professional guides suggest disconnecting the 12V battery as a precaution.

1. Preparation​

• Lift the vehicle using a jack and stands or a professional lift. Ensure the car is perfectly level; an angled car will result in an incorrect oil level reading.
• Remove the plastic undertray (engine splash guard) to access the transmission casing.

2. Draining the Old Fluid​

• Locate the drain plug at the bottom of the transmission (usually an 11mm or 8mm hex/Allen bolt depending on the specific revision).
• Place a drain pan underneath and remove the plug.
• Allow the fluid to drain completely. Inspect the magnetic tip of the plug for excessive metal shavings (fine "sludge" is normal; large chunks are not).
• Clean the plug and reinstall it with a new crush washer.

3. Locating the Fill and Level Ports​

• The Fill Port is typically located on the top or upper side of the gearbox, often tucked under the air intake or coolant hoses.
• The Level Check Plug is located on the side of the transmission housing.

4. Refilling​

• Remove the fill plug.
• Using a fluid pump or a long funnel with a hose, begin adding the new DEXRON DCT fluid through the fill port.
• Continue filling until fluid starts to trickle out of the Level Check Plug hole on the side.
• Once it reaches a steady drip-turn-trickle, the transmission is at the correct level.

5. Finishing Up​

• Reinstall the level check plug and the top fill plug.
• Clean any spilled oil from the transmission casing (to help you spot future leaks).
• Reinstall the undertray and lower the vehicle.
• Start the car and shift through the gears (P-R-N-D) while stationary to circulate the fluid.

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Pro-Tips​

• Temperature Matters: For the most accurate level check, the transmission fluid should be warm (but not hot), typically between 35°C and 45°C.
• Fluid Quality: Do not use standard ATF (Automatic Transmission Fluid). The PHEV unit requires specific DCT friction modifiers to handle the internal clutches of the EDU. Using the wrong fluid can cause "shuddering" or damage the electric motor interface.

 

[pdm1]

Absolutely fantastic.