Engines need a transmission to transfer power from the engine to the rest of the powertrain. Without a functional transmission, you won’t be going anywhere anytime soon. In vehicles with an automatic transmission, fluid is required to shift gears smoothly, cool the transmission, and turn mechanical energy into hydraulic energy. Fluid is transported through transmission cooling lines because this process generates a lot of heat, but unfortunately, they’re prone to damage because they run along the bottom of your vehicle.

Automotive repairs often fluctuate in price based on the mechanic, the cost of parts, and even where the part is located. For this reason, it’s a good idea to get a comprehensive understanding of what a repair should cost before you visit a technician. Read on to learn about how much it costs to replace a transmission cooling line.

What Is a Transmission Cooling Line?

Transmission cooling lines are rubber hoses that carry transmission fluid away from the transmission, through the vehicle’s radiator, and back to the transmission. The purpose of cooling lines is to cool the fluid before sending it back to the transmission, which prevents it from overheating. Without the necessary cooking, transmission fluid will get too hot and your transmission won’t work properly.

Additionally, overheating your transmission can cause the torque converter, gears, and other components to sustain damage. Once damaged, these parts need to be rebuilt or replaced, so a transmission must have functional cooling lines.

Do Manual Transmissions Have Cooling Lines?

No, most manual transmissions don’t have cooling lines. Manual transmissions don’t have oil pumps or other components that generate a lot of heat. A manual transmission also doesn’t need fluid to help with shifting because they don’t need fluid pressure to convert energy. That said, some manual vehicles may use one if they generate a lot of heat.

How Serious Are Bad Transmission Cooling Lines?

Bad transmission cooling lines are a serious problem. While you might not notice any issues right off the bat, transmission fluid that’s too hot will wear down your gears and other internal transmission components over time. This can also happen if one of the lines is leaking, so it’s important to check your transmission fluid cooling lines often. For these reasons, bad transmission cooling lines can go from being a minor, inexpensive issue to a much larger problem that requires your entire transmission to be rebuilt.

Can You Dive with Damaged Transmission Cooling Lines?

Yes, you can drive with transmission fluid lines if you only have a small leak; you should be able to drive yourself to the mechanic at least. That said, you should avoid driving with leaking or damaged transmission cooling lines.

The longer you drive with a transmission leak, the greater the risk of problems with your transmission. In fact, even a small leak can rapidly drain your transmission fluid levels, which results in damage to your torque converter, gears, and other internal transmission components.

Signs That Your Transmission Cooling Lines Need to Be Replaced

Transmission cooling lines can last for the full life of a transmission, but this rarely happens. Instead, it’s more likely that your transmission cooling lines will need to be replaced between 50,000 and 100,000, especially if you have problems with your radiator during this time. Therefore, it’s a good idea to start looking for the signs of failing cooling lines around this time.

It’s also important to replace your transmission cooling lines more frequently if you drive off-road often or live in an area that uses salt to melt snow or ice. Driving off-road can damage the lines because of exposure to rocks, and the salt can result in corrosion of the lines.

Learn more about what to look for below.

External Damage to the Transmission Cooling Lines

The most obvious sign that your transmission cooling lines need to be replaced is damage to the cooling lines. If you look at the cooling lines and notice punctures, bulges, or cracks, your cooling lines need to be replaced or repaired.

Another sign of damage to your transmission cooling line is rust around the nuts and bolts that hold it in place. Transmission lines can be exposed to the elements underneath your vehicle, especially if you live in an area that uses salt to melt snow or ice. Exposure to these elements can cause rust around these harnesses and brackets that can damage the transmission cooling line over time.

Transmission Fluid Leaks

Notice a puddle of red fluid or green fluid underneath your vehicle? This is a sign that you’re dealing with a transmission fluid leak. While many things can cause your transmission fluid to leak, a damaged cooling line will cause a slow leak that happens over time. You may slowly notice that your transmission fluid levels are lower than average, which can result in damage over time.

Hard Shifting

Shifting is the transmission’s primary purpose. When you have the right amount of cooled transmission fluid, your vehicle will shift harder. This is one of the biggest signs of bad transmission cooling lines because this means that you’re low on fluid or that the fluid is not cool enough to function properly in the transmission. You’ll know your vehicle isn’t shifting right when it’s jerky or doesn’t properly shift into gear when it should.

Burning Smell From the Transmission

When you smell anything burning, especially close to the cabin, it’s cause for concern. When your transmission cooling lines fail, the fluid can get too hot, and the transmission will begin to overheat, which causes a burning smell. While this isn’t always the cooling line’s fault, it’s a good time to check them.

If you’re unsure about where the burning smell is coming from, you can run the engine for a little while and check for a burning smell near the middle of the car; this is where the transmission is located for most vehicles.

Loud Noises

The transmission doesn’t make a lot of noise because it’s usually cool and lubricated, which keeps the process of changing gears smoothly. When a transmission starts to make loud noises, it’s a sign that the transmission fluid isn’t doing its job properly. If you check the transmission and notice that it has the right amount of fluid, it’s time to check the cooling lines to see if that system is failing.

These are only some of the signs of failing transmission cooling lines. These symptoms can change depending on your vehicle’s year, make, model, and even engine size.

How Much Does it Cost to Repair Transmission Cooling Lines?

The cost of repairing transmission cooling lines varies depending on what needs to be done. On average, you’re looking at a price range of $200 to $400, with the most common price from shops being right in the middle at $300. Factors that influence the cost of transmission cooling line replacement are the model of the vehicle, the type of cooling lines, and the severity of the damage.

How Long Does a Transmission Cooling Line Take to Replace?

Transmission cooling lines are important components, and it can take a professional a day or two to get the job done. If you plan on dropping your vehicle off at a shop, expect the shop to have it for at least a full day or two.

Transmission cooling lines can also take a long time to diagnose, especially if you bring your vehicle in for a transmission fluid leak. This is because a technician will have to find the leak before fixing the problem.

How Much Does It Cost to Replace Transmission Cooling Lines Yourself?

If you have the know-how to get down and dirty under your vehicle, it’s not a bad idea to replace the transmission cooling lines yourself. We only recommend going this route if you know what you’re doing to avoid making the problem worse. That said, transmission cooling lines only cost about $100, so the price comes down significantly if you plan on doing the work yourself.

It’s also important to note that you can patch a bad transmission line with a few inches of rubber hose, and full saddle clamps. If you patch a transmission cooling line this way, the cost can be less than $50. We only recommend doing this if you know how to patch rubber hoses properly, or you can make the problem worse. Additionally, the patch might not last as long as replacing the entire line.

Replace Your Transmission Cooling Lines Today

Transmission cooling lines are one of the most important parts of your transmission. If you don’t have functional cooling lines, there’s no way to remove heat from the transmission, which can damage transmission fluid, your gears, and other components in the transmission like the torque converter.

Always keep an eye out for the signs and symptoms of bad transmission lines so you can fix the problem before it gets worse. Plus, you’ll save a lot of money if you just have to replace the cooling lines and not the entire transmission.