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How to change rear differential oil on a Porsche Cayenne (2003-2010)

Maintenance Interval: 8 year or 80k miles (120k km)

Dealer Cost: ~$400

DIY Cost: ~$70

Skill Required: Beginner

Repair Time: 1 hours

Recommendation: Do it yourself

Changing your differential oil / fluid is important to keep your drivetrain smooth. While Porsche recommends owners change the differential fluid every 16 years or 160,000 miles, we believe this is too long. This is a cheap and easy do-it-yourself as long as you have the proper tools and ability to get your vehicle off the ground safely. For an overview of the procedure, check out the above DIY from the YouTube channel, DIY Dan. Detailed steps, parts, and tools required can be found below.

This service applies to: 

2003 - 2010 Porsche Cayenne (all models)

General tools you'll need for the job:
↗️Mechanic's tool set
↗️Low profile jack 
↗️Flat top jack stands
↗️Wheel chocks
↗️3/8" torque wrench
↗️Stubby allen key set
↗️Allen bit set
↗️Fluid transfer pump
↗️Drain pan
Torque specs and capacities:
  • Drain and fill bolts: 26 ft-lbs
  • Rear differential gear oil capacity: 1.4 liters
Vehicle-specific parts required:
Rear differential - 2 liters required
Fits all 2003 - 2010 Porsche Cayenne models
Also, purchase 2 new drain / fill plugs
Instructions:
  1. Starting with a cold engine, drive car lightly for 3 minutes to get the drivetrain fluid warmed up. This will make it easier to drain the differential fluid.
     

  2. Gather required tools and parts and put on gloves and eye protection.
     

  3. Raise your vehicle on all four corners using a jack and jack stands, so you can work under the car. Be sure to keep your vehicle level. Alternatively, if you have air suspension, just raise your car to the highest setting.
     

  4. Crawl under the rear of the vehicle and locate the rear differential. You should see two 8mm hex bolts. The one on the bottom is the drain bolt. The one located higher is the fill bolt.
     

  5. Begin by removing the fill bolt; if an 8mm bit & ratchet will not fit, use a stubby 8mm allen key, which you can find the link to in the tools section above. If you cannot get the fill bolt off, STOP and do not proceed with the procedure.
     

  6. Place a drain pan under the drain plug and remove the drain plug using an 8mm bit or allen key. Allow the differential to drain for 10 minutes.
     

  7. Install a new drain plug (the one on the bottom), which can be purchased here, and torque it to 26 ft-lbs. If you do not have a new drain plug, inspect your old drain plug for damage. If it looks okay, clean it up and re-use it.
     

  8. Now, fill your differential via the fill port. The capacity is ~1.4 liters. Attach the fluid pump to your container of gear oil and pump fluid into the differential until it starts to overflow out of the fill port; this indicates the differential is at capacity.
     

  9. Install a new fill / drain plug and torque it to 26 ft-lbs. If you cannot fit a torque wrench in, tighten the fill bolt with your stubby allen key to what feels like 26 ft-lbs. A new fill / drain plug can be purchased here.
     

  10. Lower your car.
     

  11. Clean up your workspace and put all of your tools and supplies away.
     

  12. You're all done!