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How to change transfer case oil on a Porsche Cayenne (2003-2010)

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

Dealer Cost: ~$400

DIY Cost: ~$60

Skill Required: Beginner

Repair Time: 1.5 hours

Recommendation: Do it yourself

Changing your transfer case oil is important to keep your drivetrain smooth. While Porsche recommends owners change the transfer case 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
↗️Allen bit set
↗️Fluid transfer pump
↗️Drain pan
Torque specs and capacities:
  • Drain and fill bolts: 20 ft-lbs
  • Transfer case oil capacity: ~ 0.75 liters
Vehicle-specific parts required:
Transfer case oil (same as ATF) - 1 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. Remove the front underbody panel, so you can gain access to the transfer case. The underbody panel is held on by several T30 torx bolts, which can also be removed using a 10mm socket.
     

  5. Crawl under the vehicle and locate the transfer case (towards middle of vehicle). You should see two 8mm hex bolts. The one on the bottom is the drain bolt. The one located higher is the fill bolt.
     

  6. Begin by removing the fill bolt using an 8 mm socket and a ratchet; if you have issues loosening the fill bolt, apply some heat to it. If you cannot get the fill bolt off, STOP and do not proceed with the procedure.
     

  7. 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.
     

  8. Install a new drain plug (the one on the bottom), which can be purchased here, and torque it to 20 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.
     

  9. Now, fill your transfer case via the fill port. The fill capacity is ~0.75 liters. Attach the fluid pump to your container of transfer case oil (same as ATF) and pump fluid into the transfer case until it starts to overflow out of the fill port. When this happens, the transfer case is at capacity.
     

  10. Install a new fill plug and torque it to 20 ft-lbs. Again, if you do not have a new fill plug, make sure your old fill plug is in good shape before re-using. A new fill / drain plug can be purchased here.
     

  11. Re-install the underbody panel and lower your car.
     

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

  13. You're all done!