About 9 quarts of engine oil.
The 2008 Cayenne with the 3.6 L V6 uses a wet-sump lubrication system. For a standard drain-and-fill with a new oil filter, the official capacity is typically around 9.0 quarts (roughly 8.5–9.5 qt depending on filter and measurement method). Always confirm the exact figure in your owner's manual or with a Porsche dealer, as small variations can occur by production batch or service procedure. Use a synthetic oil that meets Porsche A40 specifications (commonly 5W-40) for this engine.
Capacity details and practical notes
How you arrive at the final measurement matters. The quoted figure covers a full drain and refill with a new filter. If you perform an alternate drain scenario or use a different filter, the amount you need to add could differ slightly. When filling, add in increments, start the engine, and recheck on the dipstick when the engine is warm and has cooled enough to read accurately.
Oil type and service recommendations
For the 3.6 L Cayenne, Porsche typically specifies synthetic 5W-40 oil that meets the A40 specification. Using the correct spec supports proper lubrication, performance, and warranty compliance. If in doubt, consult the owner's manual or a certified Porsche technician.
Summary
Bottom line: the 2008 Porsche Cayenne 3.6 L generally requires about 9 quarts of engine oil for a full drain-and-fill with a new filter. Use a synthetic 5W-40 oil meeting Porsche A40, and verify the exact capacity in the owner's manual or with a dealer. After refilling, recheck the level with the dipstick to ensure it’s within the correct range.