As with other parts of a car, transmissions are susceptible to overheating. And a transmission cooler prevents that by maintaining the right temperature and ensures smooth gear shifting.
It not only helps cool the transmission but also keeps other parts of the car cool, such as the engine. The component does so by following a specific transmission cooler flow direction.
It contains coolant that passes into the engine compartment through the radiator and is routed to the water pump. In turn, the pump removes coolant from the system, which absorbs the cylinder heat. In the end, cooled fluid will leave the system under lower pressure and return.
We will start this article by discussing the transmission cooler briefly. By the end of this article, you will be able to examine how this component functions and where it should be mounted.
Let’s jump right in!
What Is a Transmission Cooler?
As a rule of thumb, engines must operate at a cooler temperature to function properly. In a similar manner, a car’s transmission also demands a certain temperature. It varies between 175- and 200 degrees Fahrenheit.
The heavier your car is, the hotter the fluid in the transmission gets. If the liquid does not cool down, it will overheat the transmission, exceeding 200 degrees Fahrenheit.
This is where a transmission cooler comes to the rescue. It resides in the radiator and consists of fins or plates. As soon as the hot fluid contacts the cooler, it begins to cool down and returns to the transmission.
How Do Transmission Coolers Work?
To comprehend how transmission coolers work, it is necessary to understand their lines.
If you look closely at the right side of the engine near the radiator, you will see two parallel lines. They are known as the inlet and outlet lines.
An inlet line ensures that the coolant reaches the radiator promptly. On the other hand, outlet lines deliver the newly cold liquid to the heater fan.
This is how transmission coolers work to keep the transmission cool. However, various obstacles, such as clogged lines, often hinder the process.
All it takes is a single clogged line to stop the cooler from sending heat to the heat sink and outside. In that case, the coolant becomes too hot and damages nearby components.
What Is the Best Place to Mount a Transmission Cooler?
A transmission cooler’s job is to keep things cool, but that doesn’t mean it should be left in the heat. It is actually the other way around. You need to mount the item in an area with plenty of airflow.
And where do all the airflows gather? In the engine compartment, of course.
Keep in mind that we recommended mounting the cooler in the engine area but not too close to it. If the cooler sits right next to the engine, chances are it will heat up and eventually blow.
Another location for mounting the item would be the radiator area. Once again, do not place the cooler in close proximity to the radiator.
Remember that the radiator is useless if you block it with the transmission cooler. Therefore, ensure that the airflow is sufficient after installing the cooler.
What Happens If You Reverse Transmission Lines?
People tend to overlook the dangers of reversing transmission lines. In reality, this is a major mistake since it has a detrimental effect on the water pump.
And what is directly related to the water pump?
You guessed it right, the transmission cooling system. It means if you set the transmission lines backward, you end up decreasing the cooler’s efficiency.
Now let’s look at what happens when the cooler is no longer efficient.
The engine temperature is expected to rise a few degrees due to less efficient cooling. Moreover, there will be a lot of mixing up between the lines.
In the worst-case scenario, you will notice a burning smell around the vehicle. An overheated transmission shows this sign.
The radiator may also malfunction if the cooler lines are configured backward. Why?
It is because the coolant is constantly flowing from the transmission to the radiator. Since it won’t be effective anymore, the radiator will have various problems caused by the coolant.
Engine High Temperature
In the first point, we mentioned that reversing transmission lines can slightly warm the engine. Unfortunately, when the radiator malfunctions, the engine will produce a lot more heat than usual.
And if you continue to have these issues and still stick to reverse transmission, your car could suffer severe damage. Hence, it is best to act promptly and fix the lines.
How Does Bypassing a Transmission Cooler Affect Your Car?
Before we look at the effects of bypassing a transmission cooler, we should warn you against it. If you bypass the cooler, you prevent transmission from cooling down.
As a result, the transmission, as well as the other components it is connected to, heat up and suffer damage. Here are other issues you may encounter –
One of the first things that can happen is that the transmission fluid can overheat.
When it gets too hot, the transmission can fail. Furthermore, it can cause the gears to slip, resulting in stalling.
Bypassing the transmission cooler can also lead to contamination of the transmission fluid. You will have difficulty shifting your car once contamination occurs.
Moreover, the fluid’s ability to cool the transmission system will diminish with time.
Intensive Fuel Use
Last but not least, you can expect your car to be overly thirsty for fuel after bypassing the cooler. But why?
You see, fluid inside the transmission heats up more quickly when the transmission cooler is bypassed. It leads to your transmission overheating and requiring more effort as it shifts.
This additional work will consume more fuel, forcing you to spend more money on gas.
Do Rubber Hoses Work on Transmission Cooling Lines?
The majority of car owners do not realize that rubber hoses actually work on transmission cooling lines. In fact, it is one of the most effective cooling components.
However, when purchasing a rubber hose, you should consider these two factors:
It should not just be any cheap hose. You should spend a little extra money on high-quality ones.
If the hose is poorly made, it will break prematurely. And a broken hose could lead to coolant leaks, ruining the cooling system.
Furthermore, it will not be possible to cool the engine with low-quality rubber hoses.
In case you are unaware, transmission lines are rated differently. It is unlikely that your cooling line will be rated the same as another vehicle.
Thus, make sure the hose you are buying matches your line’s rating.
Frequently Asked Question
1. Should you bypass the radiator when installing the transmission cooler?
No, you should not bypass the radiator when installing the transmission cooler. As you may be aware, the transmission cooler is designed to maintain a cool transmission fluid. And the radiator contributes to dissipating the heat from that fluid. Hence, if you bypass it, the fluid fails to cool adequately.
As the article illustrates, transmission coolers play a crucial role in your car’s cooling system. Unfortunately, it cannot maintain a stable transmission temperature if the transmission cooler flow direction is incorrect.
The coolant will generally flow from the transmission to the cooler and back to the transmission. This may differ depending on the type of transmission cooler you have.