What causes transmission fluid to leak and how to fix it

Many car owners consider their braking systems to be standard equipment. Your car stops each time you come to a stop and depress the brake pedal. The braking system of your car is by far the most crucial safety component. The ability to quickly stop or slow down greatly aids in preventing problems and accidents. However, you’ll start to understand the function of the braking system when you take a detailed look at the mechanics of how it operates.

transmission fluid leak

Your braking system’s various parts all work together to keep the driver safe. As a result, maintaining them properly will be the difference between suffering from a major accident or even a disastrous event. It’s a good notion to keep in mind the significance of your braking system because of how important it is.

Well, in this article, you will get to know what causes transmission fluid to leak and how to fix it. With that being said, the answers to the following questions will be discussed:

  • What’s the function of transmission fluid?
  • How often should you change your transmission fluid?
  • What causes transmission fluid leaks in a car?
  • Is it safe to drive when a car is leaking transmission fluid?
  • How can you fix a transmission fluid leak?

Ok, let’s get started.


What’s the function of transmission fluid?

Transmission fluid lubricates the metal parts and bearings inside a car’s manual gearbox to prevent them from wearing out as they move. It not only lubricates the moving elements in an automatic transmission but also creates friction and hydraulic pressure to drive the internal components. Both manual and automated transmissions benefit from the transmission fluid’s cooling properties.

An automobile must work hard to change gears, and transmission fluid makes this process easier while keeping the car’s equipment in good condition. Unlike automatic transmission fluid, which was developed in the 1940s and has since played a significant part in cars, manual transmission oil or fluid has been around in some capacity since the invention of the automobile.

How often should you change your transmission fluid?

While many individuals are aware of the necessity of changing their car’s oil, they are not as knowledgeable about transmission fluid. Both manual and automatic transmission fluid will deteriorate and pick up dirt and debris over time. While changing your transmission fluid isn’t as necessary as changing your motor oil, for instance, it’s still vital to monitor it closely and check it periodically. The performance will suffer when shifting or engaging into gear if your transmission fluid level is low or the fluid has begun to degrade.

Due to a lack of oil, this can further raise the possibility of harming internal gears and components. Depending on your driving habits and the kind of transmission in your automobile, several manufacturers advise changing your transmission fluid every 30,000–60,000 miles. It’s crucial to remember that this can change based on the brand and type of your car. Always abide by the guidelines provided by the manufacturer for your particular car.

What causes transmission fluid leaks in a car?

The following are the major causes of a transmission fluid leak:

  • Defective Seals and Other Gaskets.
  • Deteriorated Transmission Pan Gasket.
  • Faulty Transmission Lines.
  • Misalignment.
  • Damaged Valves and Solenoids.
  • Cracks and some Other sort of Damage.

Defective Seals and Other Gaskets

The transmission system uses a variety of seals and gaskets. The front input seal and the rear main engine seal may be examples of this. An alignment issue or rubber deterioration could be to blame for a transmission fluid leak.

Deteriorated Transmission Pan Gasket

A failing or out-of-place transmission pan gasket is typically to blame for a transmission fluid leak. It serves as the seal between the bell housing and the transmission pan. It is a straightforward rubber gasket that naturally deteriorates over time and needs to be replaced on a regular basis as part of normal transmission service.

Faulty Transmission Lines

Any transmission will have many hoses and lines connecting the various parts and ensuring a steady flow of fluid throughout the system. One of the transmission lines may have a weak connection or a hole or crack that is the source of the leak.


There are situations when two parts of the transmission system are simply out of alignment. A prior repair or service may have installed or modified anything incorrectly, or things may shift as you drive.

Damaged Valves and Solenoids

When the engine is running, solenoids and valves in the transmission system control the fluid flow. A transmission fluid leak may be the result of a broken component or a malfunctioning valve or solenoid.

Cracks and some Other sort of Damage

Keep in mind that the transmission and the entire car are full of moving parts. Under strain, things can move, and extreme circumstances can cause cracks in the transmission bell housing, transmission pan, or elsewhere. Undoubtedly, this is a serious issue that necessitates the repair or replacement of the fractured portion or parts. The plain truth is that you shouldn’t overlook a transmission fluid leak whenever you find one under your car. Compared to having to replace or rebuild the entire gearbox, replacing a damaged seal is far less expensive.

Is it safe to drive when a car is leaking transmission fluid?

In order to identify it from other fluids in the car, transmission fluid is either green or red in color. Driving a car that is leaking transmission fluid is not a good idea because the car might not run well even if it may not be particularly unsafe. Although it is not particularly risky to continue driving with a leaky transmission fluid in the short term, it is advised to have this problem fixed right away to look after your automobile in the long run.

How can you fix a transmission fluid leak?

transmission fluid leak

The severity of your transmission leak and how long you drove after discovering the leak will determine how serious your transmission repair is. Transmission leaks are often expensive problems that keep your automobile in the shop for several days. They don’t have to be with BlueDevil Transmission Sealer. This effectively manufactured sealing solution will quickly stop leaks and repair your transmission! The sealant will help your transmission get back in shape for a fraction of the cost and time of a trip to your local service center.

Related Article

You can watch the video for a more clearing understanding of how to fix a transmission fluid leak:


Can you drive with transmission fluid leaking?

A transmission leak won’t go away by itself. If it’s left unchecked, your car’s performance may soon suffer, and you might have to pay for a costly repair. It is therefore not recommended to drive with a leaky transmission, even though it may be safe to do so. You should therefore not put off correcting the issue.

What are the 5 common causes of transmission fluid leaks?

Five Reasons Why Transmission Fluid May Leak:

  • Drain plug or worn-out transmission pan. Transmission parts are prone to wear and tear, such as the transmission pan and drain plug.
  • The transmission Seal is Broken.
  • Transmission Pan Gasket Fault.
  • Torque converter damage.
  • Fluid line with cracks.

Is it expensive to fix a transmission fluid leak?

A new torque converter can cost over $1,000 while replacing a seal can cost as low as $150 to repair a gearbox fluid leak in a car.

Why does the transmission fluid leak?

The transmission fluid lines may crack or break over time as a result of heat and road debris, which could lead to fluid leakage. Your car’s torque pump developing a crack or a weakened axle seal are two more causes of fluid loss.

What are the signs of a transmission leak?

Here are signs that will help you Determine If Your Transmission Is Fluid Leaking:

  • Examine the dipstick.
  • Warning indicator on the dashboard.
  • Fluid Leaks.
  • Grinding Gears.
  • Clunking noises.
  • Unusual Vibration.
  • Burning Smell.
  • Acceleration Delay.

What damage can a transmission leak cause?

If neglected, even a small fluid leak can result in transmission failure. Insufficient fluid circulation will cause the transmission to malfunction and cause various sections to lose essential lubrication. The color of transmission fluid is often red, making it quite simple to recognize.

Where is the most common for a transmission to leak?

Here are the three most typical locations for a transmission fluid leak:

  • Transmission Pan Gasket. The gearbox pan’s gasket is prone to deterioration and cracking, especially in the presence of intense heat.
  • Cooler Lines. Due to debris and heat exposure, the cooler lines may eventually wear out and break.
  • Seals.

Can a transmission leak be repaired?

If the issue is a transmission leak, a straightforward reseal service and transmission fluid flush will take care of the issue. However, you’ll undoubtedly need a replacement transmission for your car if your transmission is seriously harmed.

How do I know if my car is leaking oil or transmission fluid?

Here are some useful hints for determining typical auto fluids and the likely location of leaks.

  • Engine oil is a light brown to black color.
  • The fluid for the transmission is red or brown.
  • The power steering fluid is either clear, red, or brown.
  • Brake fluid is transparent yellow to brown.

What color is transmission fluid when it leaks?

Reddish brown

Leaks in transmission fluid are often brown in color with a thicker viscosity (old fluid) or reddish brown with a thinner viscosity (fresh fluid). These leaks are often located close to the center of your car.

What happens if you don’t fix the transmission leak?

Regularly check the level and top it off as necessary. Keep in mind that a significant fluid loss can harm the gearbox or prevent you from shifting the automobile into gear.

What happens if you leak too much transmission fluid?

Similar to how flowing through water slows down the rotating crankshaft, too much fluid prevents adequate lubrication and cooling. High quantities of fluid produce a frothy material that saturates the transmission when it mixes with the air above. Pitting in part may result from this.

Final words

A damaged pan gasket is one of the main reasons for transmission leakage. You will need to repair the gasket if it becomes frayed since the fluid within will keep leaking. Fixing this issue is simple. All you need to do is spend some money on a new gasket, which is not that expensive. Ensure the pan’s bolts are sufficiently tightened as well. If they aren’t, there might be a leak. After changing the transmission fluid, the pan is frequently not fastened securely, which results in a transmission leak. Here, all you need to do is just tighten the bolts, which is an easy task. But if this problem is not resolved quickly away, much harm could result.

That concludes this article, in which we looked at what causes transmission fluid to leak and how to fix it. With that being said, the answers to the following questions were discussed:

  • What’s the function of transmission fluid?
  • How often should you change your transmission fluid?
  • What causes transmission fluid leaks in a car?
  • Is it safe to drive when a car is leaking transmission fluid?
  • How can you fix a transmission fluid leak?

Hope it was helpful. If so, kindly share it with others. Thanks for reading; see you around!