Changing the oil in your PDK transmission is important to keep your drivetrain smooth. Over time, the oil loses its critical properties, so regular replacement of the oil is essential. The PDK transmission is a combination of a manual and automatic transmission. As a result, the transmission uses both manual transmission oil and automatic transmission fluid (ATF). This is a source of confusion for many Porsche owners because Porsche calls for both a “PDK transmission oil change” and a “PDK clutch oil change”. This article is on the PDK transmission oil, which uses manual transmission fluid. You DO NOT want to put ATF fluid into the wrong part of the transmission.
Changing the PDK transmission oil is not a complicated job and is just like changing out the oil on a normal manual transmission or differential. This is a practical do-it-yourself job as long as you have some experience working on cars, the proper tools, and the ability to lift your vehicle off the ground safely. Before you get started, check out the video from YouTuber, Verus Engineering to get an overview. While this video covers how to change the PDK transmission oil on a 987, the process is the same on a 981. Detailed step-by-step instructions for the PDK can be found below.
Note: The PDK transmission oil and PDK clutch oil services have a lot of overlapping work. So, if you want to save time and money, we recommend you have both services performed at the same time.
- Mechanic’s Tool Set
- Metric Hex Bit Socket Set, 3mm to 10mm
- 1/4 Inch Drive Click Torque Wrench (20-200 in.-lb.)
- 3/8 Inch Drive Click Torque Wrench (10-80 ft.-lb.)
- K Tool International Low Profile Jack (3.33 Ton)
- ESCO 10499 Low Profile Flat Top Jack Stands (Pair) (4 required)
- Wheel Chocks
- Oil Drain Pan, 16 Quarts Capacity
- Fluid Transfer Pump Kit
- Disposable Gloves
- Safety Glasses
Oil fill plug: 20 ft-lbs
Oil drain plug: 20 ft-lbs
Differential drain: 7.5 ft-lbs
Transmission oil capacity: 2.95 liters
Step 1: Prepare your vehicle and work area.
- Starting with a cold engine, take your car for a 5 minute drive to warm up the transmission oil. This will help the oil drain more easily.
- Put on eye protection and gloves.
- Park your car on a level surface.
- Gather parts and tools.
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 is nearly the same except for jacking the rear.
- To get the rear of the 981 on jack stands, jack the rear where the sway bar mounts to the chassis. Be sure to use a jack pad to prevent damage.
- Once your car is on jack stands, give your car a hard shove to make sure it is secure.
Step 3: Remove the PDK transmission oil fill bolt
- Note: It may be necessary to remove the metal support plate under the transmission to gain access to the fill and/or drain bolt. If it is, you can remove the transmission cover by removing the 15mm fasteners and loosening the fasteners on the diagonal braces as shown in the video. DO NOT allow your vehicle to rest on the wheels with the support plate and diagonal braces loosened or removed.
- Locate the oil fill plug at the passenger side of the gearbox housing, behind the CV axle as shown in the video. Note: In the video, the fill plug is referred to as the “fill for the rear differential”.
- Use a ratchet, appropriate extension and an 8mm Allen key socket to break loose and remove the plug.
- If you cannot remove the fill plug, STOP AND DO NOT PROCEED as you will not be able to add new oil.
Step 4: Drain the differential oil
- The PDK transmission oil supplies both the gear set and differential, so you will need to begin by draining the differential oil.
- Locate the differential oil drain plug at the bottom of the transmission pan, towards the front of the vehicle.
- Break loose the drain plug using a 5mm hex bit socket and ratchet, but don’t remove it yet.
- Position an oil catch pan underneath the transmission and remove the oil drain plug. Make sure to catch it before it falls into the oil catch pan.
- Let the oil drain for 15 minutes.
- Reinstall the oil drain plug and torque it to 7.5 ft-lbs using a torque wrench
Step 5: Drain the PDK transmission oil
- As shown in the video, locate the oil drain plug for the transmission at the bottom of the transmission pan towards the back of the vehicle.
- Break it loose using a ratchet and an 8mm Allen key socket, but don’t remove it yet.
- Position the oil catch pan underneath the transmission 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 10 minutes.
- Reinstall the oil drain plug and torque it to 20 ft-lbs using a torque wrench
Step 6: Add new oil to the manual transmission
- Place a oil catch pan under the fill hole.
- Use a fluid pump to add ~2.95 liters of new oil into the housing through the fill hole, like shown in this video from this video from BleepinJeep.
- Once the oil begins to spill out of the fill hole, stop adding oil.
Step 7: Ensure PDK transmission oil is filled to the correct level
- Start the car and shift the gearbox lever through the R-N-D while pausing for one second at each position.
- Put the gear lever into Park.
- Go back underneath the car and add more fluid until it starts spills out.
- Refit the oil fill plug and tighten it to 20 ft-lbs with a torque wrench.
Step 8: Reinstall everything in reverse
- Ensure there are no fluid leaks.
- If the metal support plate was removed, reinstall it and torque it as follows:
- Torque support plate fasteners to 48 ft-lbs.
- Torque fasteners that connect the diagonal braces to the support plate and rear axle cross member to 48 ft-lbs.
- Torque fasteners that connect diagonal braces to vehicle body to 22 ft-lbs, then tighten them an additional 1/4 turn.
- 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.
- Note: If you the metal support plate was removed, Porsche states that you will need to get an alignment.
