Transmission Pump: Symptoms Of Failure & Replacement Costs

If you drive a car with an automatic transmission you should know the bare minimum about the transmission pump. We are strong believers in knowing what makes your car “tick”. A transmission pump is a crucial part of any automatic transmission (DSG, CVT or standard) which makes it extremely important to know the early symptoms of failure.

In this article we touch upon the very basics like what the transmission pump is and what does it do. Additionally, we also take about how you can tell if your transmission pump is starting to fail and what the signs and symptoms of a bad transmission pump are. You will also learn how much it costs to either repair or replace the transmission pump. Stay with us.

What Is A Transmission Pump And What Does It Do?

A transmission pump is one of the most important parts of an automatic transmission. The transmission pump is responsible for providing fresh and filtered transmission fluid to all the internal components of an automatic transmission. A transmission pump is usually placed in the center or the front of the transmission. 

In a standard automatic transmission, it is placed in between the torque converter and the planetary gear sets. A transmission pump consists of an electric motor and a pump assembly which is driven by the power of the engine. The electric motor takes care of more than just the transmission pump. It makes sure that the torque converter and the band brakes function properly as well. You can imagine the amount of stress all the internal components of an automatic transmission go through. Without a constant flow of cool and fresh transmission fluid, your transmission would quickly be destroyed.

What Causes Transmission Pump Failure

The most common cause of a failing transmission pump is overheating and an insufficient amount of transmission fluid. A failed electric motor that runs the transmission pump is also a common cause of transmission pump failure.

Overheating can occur when a driver puts too much stress on the transmission while driving, however, a transmission pump can also overheat if it has defective cooling fins. In order for the transmission pump to work properly, there must also be enough transmission fluid in the transmission. If there is not enough transmission fluid, the transmission pump would quickly overheat and fail. 

Water contamination of transmission fluid is also a big problem when it comes to the well-being of the transmission pump. Seized bearings in the transmission can come as a consequence of both water contamination and overheating. Additionally, damaged or worn-out seals on the transmission pump can also lead to a complete failure. 

We always talk about the importance of replacing your transmission fluid, we talked about it in our article about the 14 signs of transmission problems and in our article about hard shifting automatic transmissions. We don’t mind repeating ourselves yet again. If the transmission fluid is old and worn out, it cannot properly lubricate all the moving parts inside an automatic transmission. This leads to increased wear of all the internal parts of the transmission, including the transmission pump. Furthermore, it also contributes to overheating of the transmission which again damages the transmission pump.

How To Tell If Your Transmission Pump Is Bad

Now you know what makes the transmission pump fail. It is now time you learn how to recognize and diagnose the early symptoms of a bad transmission pump. The key thing to remember here is that none of the symptoms we list are to be ignored. If you wait too long, a complete failure of a transmission pump can also lead to a complete failure of the transmission as a whole. You do not want to be dealing with that, trust us. It is much cheaper to fix the transmission pump.

Symptoms Of A Bad Transmission Pump

  • Gear changes are not as smooth as they were
  • Transmission is slipping
  • There is a weird odor present
  • Your check engine or check the transmission warning light comes up
  • Transmission becomes noisy
  • Your transmission breaks down completely

Signs Of A Failing Transmission Pump

  1. Gear changes are not as smooth as they were

In order to keep gear changes smooth and comfortable, your transmission relies on the transmission pump to deliver the transmission to all the moving parts of the transmission. This includes the torque converter and the gear sets. When the transmission pump starts failing, your gear changes become much rougher and jerky.

  1. Transmission is slipping

In order for the transmission to operate smoothly, there needs to be an appropriate amount of pressure in the transmission. As the transmission pump starts failing, the transmission is unable to keep that level of pressure. As a consequence, the transmission starts slipping and the gear changes are not accurate.

  1. There is a weird odor present

If the transmission pump is not capable of keeping a flow of fresh transmission fluid throughout the transmission, things are about to get hot. Literally. When the transmission starts overheating there should be a distinct burnt odor both around your car and even in the interior of your car. Your car should alert you about the overheating transmissions and you should stop driving immediately!

  1. Your check engine or check the transmission warning light comes up

Every modern car should illuminate the “check engine” or “check transmission” light as soon as it detects problems with the transmission pump. There are sensors in place that monitor the flow through the transmission pump. As the sensors detect insufficient flow rates, they should alert the car of potential problems. 

  1. Transmission becomes noisy

A healthy automatic transmission should be completely silent. There should never be any signs of grinding, screeching, or other noises coming from the transmission.

Transmission Pump Whine

A typical sound of a failing transmission pump is universally described as a “whining” noise. Although whining noises can be caused by other faulty transmission components, it is typical for a bad transmission pump to make whining noises.

  1. Your transmission breaks down completely

If you failed to notice or decided to ignore all the signs and symptoms of a failing transmission pump that we listed above, you are probably going to experience a complete breakdown of the transmission. From this point forward you can only replace the transmission in its entirety and hope you get the best deal possible. It’s not going to be cheap, let me tell you that.

Do This To Prevent The Transmission Pump From Failing

  1. Regularly replace the transmission fluid
  2. Regularly replace the transmission filter
  3. Do not overload the transmission
  4. Do not overstress the transmission
  5. Recognize changes in your transmissions behavior

The number one thing and the most important thing you need to do is regular transmission servicing. A regular replacement of the transmission fluid and the transmission filter is the key to a long life of a transmission pump. Make sure you also monitor the state and the levels of your transmission fluid during the service interval. Ask your mechanic to do it for you if you are not capable yourself.

Your car has a towing limit for a reason. By overloading and torturing your engine and transmission, you are bound to be met with transmission pump problems. Respect your car’s limits.

If you do a lot of off-road driving or driving in the snow, make sure you are giving your transmission enough time to cool off. Overstressing the transmission, even in stop-and-go traffic can lead to overheating and eventually damage to the transmission pump.

Replacement Costs

Estimating the replacement cost of a new transmission cost varies greatly by the price of labor in your location and the car you are driving.

Generally speaking, replacing the transmission pump can cost you anywhere from 300$ to 1500$, this includes the labor cost. It varies greatly by the model and makes of the car and the labor costs in your country or city.

Frequently Asked Questions

How To Fix The Transmission Pump Whine?

There is no magical solution for fixing a transmission pump whine. A complete rebuild or a replacement transmission pump is the only option. If the transmission pump is completely destroyed, the only and in many cases the best option is to replace it with a new one.

What Tools Do You Need To Remove A Transmission Pump?

Apart from the usual tools that are needed to remove and open the transmission, you will also need a transmission pump puller.

What Is The Expected Lifetime Of A Transmission Pump?

A transmission pump should last the lifetime of the transmission and the car. However, this is only true if the transmission has been regularly serviced. Bad driving habits and worn-out or low levels of transmission fluid will destroy the transmission pump prematurely.

Should You Drive With A Bad Transmission Pump?

Absolutely not! Driving with a bad transmission pump can lead to a complete failure of the transmission pump and eventually a complete breakdown of the transmission. As soon as you recognize the signs of a bad transmission pump, you should book an appointment with a transmission specialist.

What Happens When A Transmission Pump Goes Out?

As the transmission pump goes out, your transmission is deprived of a fresh flow of transmission fluid on the crucial internal moving parts of the transmission. Due to the lack of pressure in the transmission, the gear shifts become extremely rough. If you continue driving with a malfunctioned transmission pump you are at risk of a complete transmission failure.

Can You Rebuild Or Fix A Transmission Pump?

Yes, there are rebuild kits for certain transmission pumps. Based on the state of the transmission pump, your mechanic will determine if a repair is possible or if a complete replacement is needed.

Conclusion

By this point, you are well aware that a transmission pump is to a transmission like a heart is to a human. Transmission fluid needs to be pumped around the transmission like blood. Without the transmission pump, things go wrong extremely quickly and you should never, and we mean never ignore the symptoms of a failing transmission pump. Let’s recap.

Symptoms of a failing transmission pump include:

  • Rough gear changes
  • Slipping of the transmission
  • The smell of burning oil/transmission fluid
  • The check engine or check the transmission warning light comes up
  • Transmission makes a whining noise
  • Transmission breaks down