If you own a 2003 or 2004 Mustang Cobra I hope you know that is supercharged from the factory. With this information you obviously know it has some upkeep that is needed from time to time. The 2003/2004 Cobra is equipped with a Eaton M112 Roots Supercharger that has its own self contained oil. Ford recommends servicing by changing the oil at 100,000 miles. I personally would rather do it more regularly to keep an eye on any issues that may arise.

Level of Difficulty
On a 1-10 this job gets a 1. This is very easy and doesn’t take long to do.

Maintenance Schedule
Ford recommended a change at 100,000 miles but I would strongly suggest every 50,000. If the supercharger has a smaller pulley on it I would recommend at least every 30,000 if not 15,000. It is a very easy and quick thing to do and you can see any coming signs of issues if the oil is burnt or what have you.

Items Needed

• Supercharger Oil (about 8-10 ounces) – Ford is most expensive, the GM is said to be identical.
• Fords Part number E9SZ-19577-A
• GM Part number 1234-5982
• Some supercharger porting businesses recommend Mobile 1 full synthetic 10w30
• Syringe for sucking out and refilling the oil
• A clear plastic flexible tube for attaching to the end of the syringe
• A container to hold the old supercharger oil
• A rag to keep any oil dripped from getting on anything
• A jack to raise the rear of the car or ramps, not needed but helps to get more oil out
• A bit to remove the bolt to gain access to the oil

Syringe (I found mine at WalMart)

Plastic Tubing (WalMart Automotive)

Step 1 – Jack up the vehicle
You do not have to do this, I recommended it. I wouldn’t use ramps since you need to lower the car back to fill the oil back up. You don’t need to crank the car with no oil in the supercharger.

Step 2 – Place a rag under the supercharger bolt hold you will remove
This keeps any oil that may come out from getting on your engine.

Step 3 – Remove supercharger bolt, some oil may come out but not much.
Slowly break it loose and remove it, Be careful not to drop it.

Supercharger Oil Fill Plug Location

Step 4 – Suck out the old oil
Use the plastic tube and attach it to the end of the syringe. Slowly push the plastic tube (you can cut it to about 8-10 inches long if you wish) into the supercharger where the fill plug was. It should go downward. You don’t have to go all the way down yet. Slowly suck out the oil, it will take a while. Once you are done to make sure you have all of the oil that you can get you can try to push the tube to the very bottom of the fill area to get any remaining oil.

Step 5 – Lower the car back down
Do not crank the vehicle to do this. Once on the ground you will be ready to fill the supercharger oil back up.

Step 6 -Fill the supercharger oil
Clean out the syringe and plastic tube with a bit of the oil you have to remove any old oil. Make sure you keep the syringe free from debris. Slowly fill the supercharger back up with oil. It will be hard to know when you have put enough oil in it as it cant run out of the fill plug hole with the plastic tube in it. After you remove the plastic tube be ready to catch any oil that may run out. Once the supercharger is full (oil coming out of the supercharger fill plug while car is level, there should be 8-10 ounces of oil in it) recap the fill plug.

Step 7 -First time driving after change
Listen for any odd noises and take it easy on it for a little bit. After a small drive check the bolt to make sure its still tight (let the engine warm/cool) and wipe any oil away that may have came out.