Changing your front differential oil is important to keep your drivetrain smooth. Over time, the oil loses its critical properties that prevent metal on metal contact. This is a easy do-it-yourself as long as you have the proper tools and ability to get your vehicle off the ground safely. If you are unsure of how to do this procedure, please visit a certified mechanic.
For an overview of the procedure, check out the above DIY from the YouTube channel, RandomCar. While the video is for a Porsche 996 Turbo, it also applies to other 996 all-wheel drive trims. Detailed steps, parts, and tools required can be found below.
Front differential oil capacity: 1.5 liters
Differential fill plug (17mm): 21 ft-lbs
Differential drain plug (17mm): 21 ft-lbs
Step 1: Prepare your vehicle and work area
- Starting with a cold engine, drive your car lightly for 5 minutes to get the drivetrain fluid warmed up; this will make it easier to drain the differential fluid.
- Park your car on a flat surface.
- Gather required tools and parts.
- Put on gloves and eye protection.
Step 2: Raise your vehicle off the ground
- To give yourself enough clearance to work, safely raise your vehicle using a lift or jack and jack stands.
- ENSURE YOUR CAR IS LEVEL! This is essential to ensure the correct fluid level.
- NEVER rely on a jack to keep your car up; use jack stands to safely support your vehicle.
- Also be sure to use wheel chocks to prevent your car from rolling.
- To lift your vehicle on jack stands, check out this helpful video from CarFanatic.
- While it is for the Porsche 997, the procedure for the 996 is the same.
- Once your car is on jack stands, give your car a hard shove to make sure it is secure.
Step 3: Remove the front underbody panel
- Get underneath the front of the vehicle.
- Undo the bolts and gently pry off the clips that hold the underbody panel in place.
- Remove the underbody panel to gain access to the front differential.
Step 4: Remove the front differential fill plug
- Locate the front differential fill plug, which is located on the passenger side of the differential and next to the front axle.
- Use a 17mm socket to remove the fill plug.
- If you cannot remove the fill plug, STOP AND DO NOT PROCEED as you will not be able to add new oil.
Step 5: Drain the front differential oil
- Locate the drain plug, which is on the rearmost part of the differential.
- Use a 17mm socket to break the drain plug loose, but do not fully remove it.
- Position an oil catch pan underneath the differential and remove the oil drain plug. Make sure to catch it before it falls into the oil catch pan.
- Let the oil drain for at least 15 minutes.
- Reinstall the drain plug and torque it to 21 ft-lbs with a torque wrench. Note: The drain plug does not use a sealing ring.
Step 6: Fill the rear differential with new gear oil
- Note: Before filling the differential, make sure the vehicle is level so you can fill the oil to the correct level.
- Add ~1.5 liters of transmission fluid in the fill bolt hole using a fluid transfer pump as shown in this video from BleeingJeep.
- Once oil begins to drip out of the fill hole, you’ve reached the correct oil level.
- Refit the fill plug and tighten it to 21 ft-lbs with a torque wrench. Note: The fill plug does not use a sealing ring.
Step 7: Lower your vehicle back on the ground
- Lower your vehicle back on the ground.
- Clean up your work area and put away your tools.
- Save the used oil in a container, so you can recycle it at your local auto parts store.