Transmission Pan: The Definitive Guide

As you know, automatic transmissions need a transmission pan in order to hold all of the ATF (automatic transmission fluid). That ATF is needed for fluid pressure, lubrication, and cooling. But did you know they do more than just act as a container? Besides playing an important role for your vehicle, there are also many different types of transmission pans you can install besides the stock pan. Some can actually help to improve the transmission’s performance. For example, deep pans can help tremendously with cooling since your transmission is able to contain more ATF. So today, we’ll be going over more of what you should know about the transmission pan as well as the different types of transmission pans you can find.

Basics of an Automatic Transmission Pan

Function

As we’ve explained, your transmission requires ATF in order to provide necessary fluid pressure, lubrication, and cooling capabilities. Other functions include cleaning metal surfaces, preventing rust, extending temperature range, preventing fluid oxidation, and conditioning gaskets. But all of that ATF has to be held somewhere though, which is exactly what the transmission pan is for. Besides holding ATF, they are also meant to:

  • Protect the ATF from foreign contaminants
  • Collect any dirt or particles in the ATF through the pan’s magnet
  • Prevent objects on the road such as rocks from springing a leak
  • Help cool the ATF before it goes back into the transmission
  • The transmission pan gasket prevents any fluid from leaking out

Capacity

The average automatic transmission holds about 12 quarts of transmission fluid, but larger or more powerful vehicles have transmissions that can hold up to 36 quarts! A transmission oil pan holds about half of the total amount of transmission fluid, while the rest remains in the torque converter and transmission itself. As you can guess, transmissions that require more ATF means that these transmissions work harder in order to handle the vehicle’s engine power. Transmissions that hold more ATF also provides more cooling capability.

Common problems

You know automatic transmissions have their fair share of problems, and transmission pans are no exception. Although a transmission oil pan might seem too simple to develop any problems, they actually can and they are more common than you might think. Problems that can occur with transmission pans include:

  • Large objects can strike the transmission oil pan, potentially causing a puncture that will have ATF leaking out. A big enough hole can cause a large amount of fluid loss in a small amount of time. This results in very erratic transmission behavior
  • Pan gaskets can slip out of position or crack from age, which will also cause fluid to leak out
  • Loose transmission pan bolts or drain plugs can also cause a leak
  • Using a floor jack to lift a vehicle by the pan can cause a large dent that results in reduced fluid capacity

How to take care of a transmission pan

There are some basic maintenance steps we can take to make sure our transmission pan keeps working as it should. Some best practices to keep in mind include:

  • Avoid using RTV sealants and cork-based gaskets to seal the pan. Cork gaskets are made of a very cheap material that cracks easily over time. Sealants on the other hand, not only creates residue that can contaminate the ATF and stick to the pan, but it also makes the pan difficult to remove the next time you need to. Stick with a reusable rubber transmission pan gasket as it prevents leaks better, lasts longer, is made of higher quality, and makes fluid changes just plain easier
  • Inspect the pan gasket each time you have a fluid change performed. If it’s warped, cracked, or broken in any way, replace it immediately with another
  • Inspect the transmission oil pan periodically for any signs of leaks or damage
  • When you have a fluid change performed, always have the pan cleaned as well as the magnet that collects metal shavings
  • Always have the transmission pan tightened to manufacturer specifications. This ensures that the pan doesn’t get damaged, the gasket doesn’t get crushed, and the bolts are tight enough to prevent any leaks
  • When tightening pan bolts, start from the center bolts and continue out in a criss-cross pattern. This ensures even pressure on all sides

automatic transmission pan identification

How to identify a transmission model by its pan

The Different Types of Automatic Transmission Pans

Now that we’ve covered what the transmission pan does, common problem that can occur, and how to take take care of it, let’s move on to the different types of pans. As you can guess, there are other transmission pans you can find besides the stock transmission oil pan. Pans can come in different varieties, depending on transmission type, material used, fluid capacity, and cooling options. If you aren’t sure what transmission your vehicle has or what pans can fit, you can use this useful tool to find out.

Stock Pans

Stock pans are what most vehicles come equipped with. Stock pans also remain closer to the transmission, which is better for vehicles that sit lower to the ground. This prevents scraping and road debris from coming into contact with it.

stock-transmission-pan-comparison

A variety of stock GM transmission pans

Stock steel – The majority of car manufacturers provide a transmission with a stock steel pan. Steel is very durable and prevents rust well, and they are often the least expensive option. If you are looking for a replacement transmission pan, you can almost always find your car’s make and model in stock steel.

Leave a Reply

Your email address will not be published. Required fields are marked *