Do You Leave the Car Running When Adding Transmission Fluid?

When it comes to adding transmission fluid, there is some debate about whether or not you should leave the car running. Some people believe that it is necessary to keep the transmission warm and circulating, while others believe that it is not necessary and can be dangerous.

In this article, we will explore the pros and cons of leaving the car running when adding transmission fluid, and we will provide you with the information you need to make an informed decision.

Pros of Leaving the Car Running

• Keeps the transmission warm and circulating. When the transmission is running, the fluid is circulated throughout the system, which helps to keep it warm and prevents it from becoming thick and sludgy. This can be especially important in cold weather, as cold fluid can cause the transmission to shift hard and jerkily.
• Helps to prevent air from getting into the transmission. When you add transmission fluid to a running transmission, the vacuum created by the running engine helps to prevent air from getting into the system. This is important because air can cause the transmission to slip and overheat.

Cons of Leaving the Car Running

• Can be dangerous. Leaving the car running when adding transmission fluid can be dangerous because it can increase the risk of the engine overheating. This is especially true if the transmission fluid level is low, as the engine will have to work harder to circulate the fluid. In some cases, the engine can overheat and seize up, which can cause serious damage.
• Unnecessary. In most cases, it is not necessary to leave the car running when adding transmission fluid. The fluid will circulate naturally through the system when the car is turned off. If you are concerned about the fluid getting cold, you can simply warm it up by driving the car for a few minutes before adding it.

Conclusion

Ultimately, the decision of whether or not to leave the car running when adding transmission fluid is up to you. However, it is important to be aware of the potential risks and benefits of each option before making a decision. If you are unsure about what to do, it is always best to consult with a qualified mechanic.