Removing The Transmission Pan: A Step-By-Step Guide

Removing a transmission pan can be a challenging task, often made more difficult by the fact that it has been several years since the pan has been removed, causing it to get stuck to the transmission due to the sealant or gasket creating a bond. This process is usually carried out for repair, maintenance or inspection. Before attempting to remove the transmission pan, it is important to drain the old transmission fluid by placing a large catch pan under the transmission pan and loosening the bolts that attach the pan to the transmission. It is also important to note that some cars require the removal of the oil pan or parts of the exhaust system before accessing the transmission pan.

Locate the transmission pan

To locate the transmission pan, you will need to crawl underneath the vehicle. The transmission pan is typically located in the undercarriage of the vehicle, attached to the bottom of the transmission. The transmission is located in different places depending on the type of vehicle you have. For front-wheel-drive vehicles, the transmission is usually situated left-to-right under the engine bay. For rear-wheeled vehicles, the transmission typically hangs under the centre console area, facing front to rear.

The transmission pan will be attached to the bottom of the transmission with six to eight bolts. It is prone to damage due to its location and can be punctured by speed bumps and road debris.

You can also identify the transmission pan by observing its shape and the number of bolts. Different types of transmission pans have different shapes, and the number of bolts can help identify the transmission type.

Place a drain pan underneath

Before placing the drain pan, it is recommended to drain the fluid from the transmission pan, especially if your pan has a drain plug. If your pan does not have a drain plug, you can leave one bolt in the pan and create a controlled spill into the drain pan. Alternatively, you can loosen the bolts on all but one side of the pan, tap the pan with a mallet to break the seal, and tilt the pan to let the fluid spill over into the drain pan.

Once the fluid has been drained, you can remove the remaining bolts and lower the transmission pan. It is important to be prepared for fluid to leak out as soon as you loosen the pan bolts.

When placing the drain pan, consider using a larger slab of cardboard underneath to catch any splatter and prevent any mess.

Loosen and remove bolts

Before you begin to loosen and remove bolts, there are a few preliminary steps to take. First, you'll need to raise the front of the vehicle with a jack and support it on jack stands. Next, locate the transmission pan—a large, metal pan on the bottom of the transmission. Place a drain pan directly under the transmission pan to catch any fluid that may leak out. Put on a pair of safety glasses to prevent debris from entering your eyes.

Now, you can begin to loosen and remove the bolts. First, spray the base of the transmission and the transmission pan with a de-greasing chemical. Wipe away the excess grease and debris from the transmission and transmission pan with a shop rag.

Next, examine the outer edge of the transmission pan and locate the transmission pan bolts. The number of bolts will vary depending on the vehicle. Loosen and remove all but two transmission pan bolts with a ratchet and socket. Loosen the two remaining transmission bolts until they are about halfway out. This will prevent the transmission pan from falling when it breaks free.

Now, examine the area where the pan and the transmission meet and locate the seam where the pan ends and the transmission begins. Place the head of a flat-head screwdriver horizontally into the seam and lightly tap the handle of the screwdriver with a rubber mallet until the head of the screwdriver penetrates the seam. Lightly pry downward to break the bond between the transmission and the transmission pan. Repeat this step on each side of the pan until it is free from the transmission.

Finally, allow the transmission fluid to flow into the drain pan, remove the last two transmission pan bolts, and then lower the transmission pan.

Use a screwdriver to separate the pan from the transmission case

To separate the pan from the transmission case, you will need a small, flat screwdriver. This is a crucial step when performing preventative maintenance or addressing a leaking gasket.

First, loosen and remove the bolts around the transmission pan, except for the corner bolts. These should also be loosened but left in place to allow the rest of the fluid to drain and to prevent fluid from splashing everywhere.

Next, use the flat screwdriver to separate the pan from the transmission case. Place the screwdriver head horizontally into the seam between the pan and the transmission case. Lightly tap the screwdriver handle with a rubber mallet until the screwdriver head penetrates the seam. Then, gently pry downward to break the bond between the transmission and the pan. Repeat this process on each side of the pan until it is completely free from the transmission.

It is important to note that this process may vary depending on your vehicle's specific make and model, so always refer to your manufacturer's recommendations and vehicle manual for guidance.

Clean the pan and replace the filter

Once the transmission oil pan has been removed, it's time to clean the pan and replace the filter.

First, examine the old transmission fluid. Look for anything unusual, such as sediment or large pieces of metal, which could indicate a larger problem. If you find anything suspicious, consult a transmission expert immediately.

Next, clean the transmission oil pan inside and out. Automatic transmissions are very sensitive to dirt and foreign matter, so use a degreaser to clean the outside of the pan and brake cleaner to clean the inside and the gasket mating surfaces. Carefully remove all the gasket material from the transmission oil pan and the mating surface on the transmission. You can use a razor blade for this step. Most transmissions have a magnet in the pan to catch small metal particles, so be sure to clean and reinstall it. Also, clean the bolts that secure the oil pan to the transmission.

Now, it's time to remove and replace the transmission filter. Most automatic transmissions have a filter that traps debris in the system, and this should be changed as part of a complete service. The filter is usually located on the bottom of the valve body and is visible once the transmission oil pan has been removed. Look for a white or yellow plastic mesh on the bottom of the filter. Some filters simply snap into place or are held on by clips, while others are held in place by bolts. Pay attention to the location and orientation of any clips, and take a picture before removing the filter to use as a reference. Apply a little clean transmission fluid to any O-rings or seals on the new filter to make installation easier.

Finally, reinstall the transmission oil pan. Apply a light coat of high-tack gasket sealant to the pan and then carefully place the gasket on top, lining up the holes. Allow the sealant to set for a few minutes so the gasket won't shift during installation. Do not use RTV silicone for this step. Carefully reinstall the pan on the transmission and tighten the bolts according to the manufacturer's specifications.

Frequently asked questions