Replacing Oil Pan Gasket On 2004 Grand Prix: Step-By-Step Guide

If you're experiencing leaks around the seal of your 2004 Grand Prix, it's time to replace the oil pan gasket. This is a maintenance task that you shouldn't put off, as oil leaks can burn up your motor. While some suggest using RTV (room-temperature vulcanizing) silicone, there are also gasket sets available that are designed for your car's make and model. These include the FEL-PRO Oil Pan Gasket OS30767R and the MAHLE Oil Pan Gasket OS32147.

The 2004 Grand Prix oil pan gasket is available in the market

Several companies manufacture oil pan gaskets compatible with the 2004 Grand Prix, including FEL-PRO, Mahle Original, Victor Reinz, and DNJ. When purchasing a gasket, it is important to verify its compatibility with your vehicle. Check the product specifications and ensure that it is designed for the 2004 model year of the Pontiac Grand Prix.

• FEL-PRO Oil Pan Gasket OS34500R
• FEL-PRO Oil Pan Gasket OS30725R
• FEL-PRO Oil Pan Gasket OS30622R
• FEL-PRO Oil Pan Gasket OS30767R, which includes a Permadry molded rubber gasket
• Mahle Original Oil Pan Gasket OS32147, which includes a molded rubber gasket
• Victor Reinz Oil Pan Gasket 10-10211-01, which is noted for its improved design
• FEL-PRO Performance Oil Pan Gasket 1800, suitable for high-performance engines with 14-bolt oil pans
• DNJ Oil Pan Gasket PG3143

These gaskets can be purchased online or at auto parts stores, and some retailers offer discounts and free shipping for eligible orders. It is recommended to consult a trusted mechanic or refer to a repair manual for guidance on selecting the correct oil pan gasket and performing the installation safely and effectively.

The gasket is attached to a baffle

The baffle in the oil pan acts as a series of 'ribs' or compartments that control the flow of oil. It allows oil to easily travel towards the oil pickup while making it difficult for the oil to move in the opposite direction. This ensures a steady supply of oil to the engine, which is crucial for lubrication and preventing excessive wear.

Some baffles feature vertical metal slots to slow down the movement of oil, while others have flaps or 'trap doors' that only open in one direction. These flaps allow oil to flow into the oil pickup chamber but prevent it from flowing out during high lateral g-force situations. This design ensures that oil remains available for the engine even during high-speed turns or manoeuvres.

Additionally, a complex baffle design may include a scraper section. This feature helps contain oil splash from the rotating crank, preventing it from travelling up into the cylinders. By incorporating a scraper, the baffle not only restricts the oil movement but also helps manage oil splashing, reducing the risk of oil foaming and vapour residue in the oil pickup.

In summary, the gasket being attached to a baffle is a design consideration to maintain oil supply and prevent engine issues. The baffle's compartments and flaps work together to direct oil towards the pickup, ensuring adequate lubrication even under high-performance or track-driving conditions.

The gasket is sealed with black silicone

When replacing the oil pan gasket on a 2004 Grand Prix, you may need to use a sealant like black silicone to ensure a secure and leak-proof fit. Here are some detailed instructions on how to use black silicone to seal the gasket:

Step 1: Clean the Surfaces

Before applying the black silicone, it is crucial to clean both the engine surface and the oil pan surface. Use a soft wire brush to remove any traces of the old gasket, ensuring that the surfaces are smooth and free of debris. You can also use a solvent like brake cleaner to remove any oil or grease buildup.

Step 2: Prepare the Gasket

Take the new gasket and rub clean oil over its surface until it is lightly saturated. Wait for about 10 minutes to allow the oil to soak in, then use a clean rag or paper towel to wipe away any excess oil from the gasket's surface.

Step 3: Apply the Black Silicone

Put on a pair of gloves and apply a thin coating of black silicone to both sides of the gasket. Spread it evenly and ensure that it covers the entire surface of the gasket. You don't need a thick bead, just a thin layer will do.

Step 4: Install the Gasket and Pan

Immediately after applying the black silicone, install the gasket and the oil pan. Torque the bolts in the correct sequence and to the specified tightness. Do not allow the silicone to start curing if you are using a plain RTV (Room Temperature Vulcanizing) silicone. If you are using a different type of silicone, follow the manufacturer's instructions for curing time.

Step 5: Allow Curing Time

After installing the gasket and oil pan, let the RTV silicone cure completely before adding oil to the pan. Typically, this curing time is a minimum of 24 hours, but always refer to the manufacturer's instructions for the specific curing time of the product you are using.

By following these steps and using black silicone to seal the gasket, you can ensure a secure and leak-proof fit for your 2004 Grand Prix's oil pan gasket. Remember to work carefully and refer to the manufacturer's instructions for any specific recommendations or precautions.

The engine has to be lifted to remove the oil pan

To remove the oil pan from a 2004 Grand Prix, the engine has to be lifted. This is because the oil pan is sandwiched and bolted into the lower right motor mount.

There are several ways to lift the engine. One way is to use a plank of wood and some cheap ratchet straps to lift the engine slightly. Another way is to use a crane from Harbor Freight, which is only $140 on sale. A third way is to use an engine hoist to lift and hold the engine.

Step 1: Break lug nuts free on the passenger-side front wheel

This step is not necessary if you have an impact gun.

Step 2: Jack up the vehicle and support it with jack stands

Use a floor jack to jack up the vehicle as high as you can and support it with jack stands.

Step 3: Remove the passenger-side front wheel

Step 4: Remove the serpentine belt

Step 5: Place a 2" x 4" wood plank from one fender to another, directly over the crank pulley

Place two small pieces of 2" x 4" wood underneath the long 2" x 4" so it rests on them, instead of the top part of the fender.

Step 6: Hook a tow strap to the rear engine hook and wrap it around the 2" x 4" wood plank and the crank pulley

Ensure the strap is taut, as it will help support the engine once you've dropped the cradle (sub-frame).

Step 7: Remove the two 15mm nuts on the bottom of the passenger motor mount

You may need to use a 16mm wrench to secure the top of the front motor mount bolt as you loosen the 15mm nut on the bottom, to prevent it from spinning.

Step 8: Remove the two 15mm nuts on the top of the passenger motor mount

Step 9: Disconnect the harness clip from the sensor in the oil pan

Step 10: Place a floor jack under the front lateral bar on the cradle

Step 11: Loosen the rear driver-side 18mm cradle bolt until it's almost all the way out, but not so much that it unthreads entirely

Step 12: Loosen and remove the rear passenger-side 18mm cradle bolt, and loosen and remove both front 18mm cradle bolts

Allow the floor jack that you placed underneath the cradle to slowly lower; this will cause the front part of the cradle to dip downward. If your tow strap/2" x 4" wood plank contraption works correctly, the engine will remain up as the cradle dips.

Step 13: Remove the 15mm bolts that secure the AC compressor to its mount, and set the compressor aside

You do not have to disconnect the lines.

Step 14: Remove the front 2-3 15mm bolts that bolt the motor mount bracket to the block

This refers to the passenger motor mount and the motor mount bracket.

Step 15: Remove the rear 15mm motor mount bracket bolts (2-3 bolts on the rear)

This is where your 15mm ratchet wrench comes in handy; it's a very tight fit.

Step 16: Remove the motor mount bracket

Step 17: Remove the 2-3 flex plate inspection cover bolts with a 10mm socket and extension

Step 18: Remove oil pan bolts using a 3/8" socket and extension

Step 19: Remove the oil pan

Be careful not to gouge either the pan's mating surface or the block's, and do not damage the pan by beating on it. Also, be aware that the pick-up tube routes into the oil pan through an oil baffle and can be tricky to manipulate.

The gasket is coated with RTV

When replacing the oil pan gasket on a 2004 Grand Prix, it is important to note that RTV (Room Temperature Vulcanizing) silicone sealant should only be used as a supplement to a gasket, and not as a replacement. RTV is typically used in corners or stepped areas on the engine to ensure a leak-free assembly. It is important to follow the manufacturer's recommendations when using RTV and to only use it in the right situations.

In the case of the 2004 Grand Prix, the gasket should be coated with RTV. This is because the gasket has a built-in windage tray and a steel oil pan. The RTV will help to create a better seal and prevent leaks. However, it is important to note that RTV should not be overused, as it can prevent the gasket from forming a reliable seal. Only a small amount is needed to fill in any gaps and create a lasting seal.

When applying RTV, it is important to use it in the correct areas. It should not be applied to the entire gasket, as this can cause permanent damage to the gasket, such as over-compression and splitting. RTV should only be used on the corners of the gasket and/or stepped casting areas that have a gap. Additionally, the assembly should be installed within five minutes of applying the RTV, and it needs time to set up and dry before the job is complete.

By following these instructions and using RTV as a supplement to the gasket, you can ensure a proper seal and prevent leaks when replacing the oil pan gasket on a 2004 Grand Prix.

Frequently asked questions