Transmission Cooler Installation | How To Install A Transmission Cooler (2024)

Do I Need To Install A Transmission Cooler?

There are a number of benefits to using a transmission cooler on your car, truck, or SUV. The biggest benefit to installing an auxiliary transmission oil cooler is that it will help do what its name indicates, which is cool your transmission fluid.

More often than not, most vehicles can utilize a transmission cooler to help prolong the life of their transmission.There are different types of transmission coolers, and each one comes in different shapes, sizes, and has their own benefit. Any type of transmission cooler you plan on installing will help reduce trans fluid temperatures. This keep your transmission in a safe operating range which in turn will allow your transmission to last longer.

Before you decide to install a transmission cooler, be sure to figure out what transmission coolers might be best for your application.

Transmission Cooler Mounting Position

Transmission Cooler Installation | How To Install A Transmission Cooler (1)

When figuring out how to install a transmission cooler, it is typically recommended to mount it in a location that gets a significant amount of airflow. Based on this, the best place to mount a cooler would be in front of the air conditioning condenser. This position will allow the trans cooler to get ample air flow while moving in addition to getting air from the engine’s cooling fans when stopped.

When installing a transmission cooler on the condenser, using a transmission oil cooler mounting kit will make the process easy and hassle free. The mounting kits come with heady duty plastic zip ties and rubber spacers. The spacers are used to space the cooler from the condenser to prevent direct contact between the two. You can find transmission mounting kits here.

In some applications however, it may be best to have a remote mounted transmission cooler that utilizes a fan to help cool the fluid. This is typically found in more extreme applications such as those who drag race or tow for example.

Where ever your cooler is mounted, it needs to get enough air flow to help keep the fluid cool.

Transmission Cooler Orientation

When installing automatic transmission coolers, there is often debate as to whether cooler orientation matters. More often than not, transmission cooler orientation does not make much of a difference. While some may argue that you need to install a certain type of cooler inverted to prevent air bubbles, the transmission line pressure it strong enough to push fluid through the entire cooler to prevent this.

Does A Transmission Cooler Go Before of After The Radiator?

Aftermarket transmission coolers are best installed after fluid has already gone through the radiator. Since hot fluid leaves the transmission then goes through the cooler inside the radiator, it makes sense to then route the transmission fluid that would go back to the transmission to the aftermarket cooler to further lower temperatures.

Can You Mount A Transmission Cooler Behind The Radiator?

It’s best to mount an external transmission cooler in front of the radiator or air conditioning condenser in order to get the most out of the installation. Since external transmission coolers rely on air flow going over their core to help lower transmission temperatures, it’s highly recommended to put it in a spot that’ll take advantage of getting as much air flow as possible.

Should I Bypass My Radiator When Installing An External Transmission Cooler?

A common question we get asked is whether it is recommended to bypass the radiator with your external transmission cooler. The easiest answer to this is, it depends. There are a number of factors that determine if you should use your trans cooler as a stand alone unit or in series with the factor radiator transmission cool.

If you live in a very warm area, it may be better to bypass the factory transmission cooler in the radiator in favor of a larger, external transmission cooler. Reason being, the radiator can act as a heater and warm the transmission fluid higher than where you may be comfortable with it operating (200 + degrees), especially if you face a lot of stop and go traffic or other harsh driving conditions.

It is recommended however to keep the factory radiator transmission cooler and use and external cooler if you live in a cooler climate. The factory cooler will help get the transmission temperature into a suitable range. When it comes to cooling your transmission, you can actually over cool it, and it may not be able to flow as well compared to warmer fluid.

Transmission Cooler Line Path & Flow Direction

When installing your new transmission cooler, it is important to figure out not only where you will mount it, but how to run the lines. In most applications where the external trans cooler is used in addition to the factory one, you will need to route the new transmission lines from the radiator to the external cooler.

The below transmission cooler installation diagram shows the transmission fluid flow direction and how the fluid will be routed through a new external cooler.

Transmission Cooler Installation | How To Install A Transmission Cooler (2)

You will need to determine which line is the return for the transmission. You want the already warm fluid to flow into the external cooler to help better control fluid temperatures, so the transmission cooler flow direction will look something like this:

Transmission out (fluid hot) > radiator cooler in > radiator cooler out > external transmission cooler in > transmission cooler out > transmission in (fluid cool).

If you plan to use rubber transmission hose and keep the stock cooler lines, you need to connect the cooler return line to your vehicle’s return line. In most cases you’ll need to make a cut to the factory line and connect the new rubber line to it. This can be done with a double sided barb fitting, or by flaring the metal line and then clamping the new rubber hose to it.

How Much Does It Cost To Install A Transmission Cooler?

Aside from the purchase of a transmission cooler, additional costs may come from extra parts such as transmission fluid, transmission hose, clamps, fittings, and mounting pieces. A number of transmission coolers come with installation kits that contain most of these items aside from fluid. However, it is recommended to figure out what you need before buying a complete kit. Most transmission cooler installation kits may not be 100% complete for your application, so it would be best to assess what you need and what is included.

If you were to just purchase the cooler then source the additional parts needed, there would not be much of an additional cost.

If you have a desire to run custom lines and AN fittings, then the cost will certainly increase. While installing basic rubber lines might work for most, in some cases, your vehicle may need custom lines, which are more costly than standard transmission lines.

Depending on the cooler you purchase and your lines, you can spend as little as $20 extra to install a cooler, or in some cases, as much as $150 or more. Ultimately, the cost to install an automatic transmission oil cooler is dependent on what your needs are.

Things To Consider When Installing A Transmission Cooler

When installing a transmission cooler in your car, truck or SUV, it is important to consider not only the cooler size, but where to mount it, and how to run the lines. Mounting a transmission cooler is typically best in front of the air conditioning condenser so it gets ample air flow. Mounting here provides significant air flow which will help keep temperatures low.

In addition, having the right parts to install a transmission makes the process easier. Many trans coolers come with installation kits that contain rubber hose, clamps, fittings, and mounting hardware. While this is great, it is best to remember that these are universal kits that may not contain exactly what you need. When you install your cooler you will need to account for adding additional transmission fluid to compensate for the increased capacity of the transmission cooling system.

An automatic transmission cooler will not only help keep your fluid temperatures lower, but improves the longevity of your transmission. For a small investment, you can save thousands in repairs needed for replacing a failed transmission due to over heating.

Transmission Cooler Installation | How To Install A Transmission Cooler (2024)

FAQs

Does it matter which way a transmission cooler is mounted? ›

Expert Reply: The Derale stacked plate transmission coolers like part # D13403 can be mounted in any orientation that you need including having the hose fittings down. The line pressure from the transmission will push all of the fluid through the cooler regardless of how it is mounted.

Where is the best place to mount a transmission cooler? ›

This will provide the most efficient transmission fluid cooling system for your vehicle. Mount the supplemental B&M SuperCooler in an area where the cooler receives good air flow circulation. The best location is in front of the radiator.

Can a transmission cooler cool too much? ›

Transmission fluid can't be cooled too much, so installing the biggest cooler that fits in your engine compartment and that provides the most cooling protection for your transmission is a good idea.

Can you mount transmission cooler behind radiator? ›

Although I recommend placing the cooler in front of the condenser and behind the grill of the vehicle, you could also mount the cooler in between the condensor and radiator or behind the radiator in front of the vehicle's clutch fan.

Is it better to bypass radiator transmission cooler? ›

IMHO it is better to bypass the built-in cooler. This is because the transmission adds heat to the cooling system, and you want the engine to run at a constant temp, but depending on road conditions, the transmission may opr may not be running hot. Therefore you want a separate cooling system fo r the transmission.

Should transmission cooler be before or after radiator? ›

Answer: We recommend installing the auxiliary cooler after the radiator to return the coolest fluid directly to the transmission. Installing the cooler before the radiator will still provide additional cooling and may be necessary in some difficult-to-access applications.

Can you mount a transmission cooler vertical? ›

Expert Reply: Yes, the core in Derale transmission cooler # D13403 can be mounted so that the lines enter and exit from the side rather than the top. There is enough pressure in the lines to push the fluid through no matter how you choose to mount it!

Are transmission coolers directional? ›

Can Transmission Fluid Flow Through Either Direction on a Transmission Cooler. Helpful Expert Reply: Either fitting of the Derale Series 8000 Plate-Fin Transmission Cooler Kit # D13504 can be used as the inlet or the outlet. The cooler can have fluid flow in either direction through it.

What temp is too cold for transmission fluid? ›

The ideal temperature for it is 175 degrees, plus or minus 25 degrees, and when the transmission gets below zero degrees, it gets too thick. The fluid can also fail to lubricate parts when it is too cold, wearing parts down unnecessarily.

How much will a transmission cooler lower the temperature? ›

Most transmission coolers, when properly selected and installed correctly will drop the fluid temperature at least 20 to 30 degrees Fahrenheit. Dropping the fluid temperature by 20 degrees Fahrenheit will potentially double the life of the fluid.

Do you need a fan on a transmission cooler? ›

Mechanical fans are almost always better than electric fans in terms of CFM or cooling power if you will. In this case an external transmission cooler is what is needed. Whether it needs it's own fan or not would require testing the temps of the fluid to find out.

What does a transmission cooler bypass do? ›

The thermal bypass is a small added valve that goes in the transmission line. When the transmission is cold, the thermal bypass will “bypass” the cooler so it can bring the transmission up to operating temperature more quickly.

How do you install a external transmission cooler? ›

The 'Right' Way To Install a Transmission Cooler - YouTube

Which way does transmission fluid flow through radiator? ›

Ever wondered what a car radiator transmission cooler looks li - YouTube

How do transmission cooler lines connect to radiator? ›

How to Replace Transmission Cooler to Radiator Line 1998-2007 Chevy ...

How much does it cost to install a transmission cooler? ›

You can have a local transmission shop install a transmission oil cooler in your vehicle. Expect to pay between $150 and $250 for the job. Either way, installing an auxiliary transmission oil cooler is one of the best investments you can make in protecting your transmission from overheating and certain failure.

Where is the transmission oil cooler located? ›

The transmission cooler is typically mounted on the radiator, where it can achieve maximum airflow. Another type of transmission cooler is sometimes mounted on the air conditioning condenser. You can also have a transmission heat exchanger, which is using coolant to cool the transmission fluid.

Are transmission coolers directional? ›

Can Transmission Fluid Flow Through Either Direction on a Transmission Cooler. Helpful Expert Reply: Either fitting of the Derale Series 8000 Plate-Fin Transmission Cooler Kit # D13504 can be used as the inlet or the outlet. The cooler can have fluid flow in either direction through it.

Can you mount a transmission cooler vertical? ›

Expert Reply: Yes, the core in Derale transmission cooler # D13403 can be mounted so that the lines enter and exit from the side rather than the top. There is enough pressure in the lines to push the fluid through no matter how you choose to mount it!

Do I need a transmission cooler for towing? ›

A transmission cooler will just help to prolong the life of the transmission by keeping the fluid cooler. Transmission fluid cannot be cooled too much, so the addition of a cooler is a good idea, especially if you are towing.

How do transmission cooler lines connect to radiator? ›

How to Replace Transmission Cooler to Radiator Line 1998-2007 Chevy ...

What is the best type of transmission cooler? ›

Stacked Plate

They use a tube to carry the ATF inside the cooler itself, while the fins are used as a passageway for the ATF as it travels through the cooler. The stacked plate is the most efficient of coolers, the most popular, and the easiest to install and remove.

Which transmission cooler line is the return? ›

The cooler of the two lines is the return line and the one to install the transmission cooler on.

Which way does transmission fluid flow through radiator? ›

Ever wondered what a car radiator transmission cooler looks li - YouTube

How much does it cost to install a transmission cooler? ›

You can have a local transmission shop install a transmission oil cooler in your vehicle. Expect to pay between $150 and $250 for the job. Either way, installing an auxiliary transmission oil cooler is one of the best investments you can make in protecting your transmission from overheating and certain failure.

Does uhaul install transmission coolers? ›

Hi Les, U-Haul installs complete tow packages including transmission coolers. For complete parts and pricing, please call or visit your local U-Haul hitch center.

How does an external transmission cooler work? ›

How It Keeps Things Cool. A transmission cooler operates like a heat exchanger mounted adjacent to your car's radiator. Hot transmission fluid flows through the unit and comes in contact with a series of fins or plates. The resulting heat dissipation cools the liquid as it cycles back into the transmission.

Will towing hurt transmission? ›

Tow trucks can damage cars when the towing process is not handled properly. Towing can even damage your vehicle's transmission, so that is why tow truck drivers take extra precautions. The driveshaft is disconnected, and front-wheel drive vehicles are towed only from the front wheels.

What should my transmission temperature be when towing? ›

To keep your transmission running at a safe temperature, keep the reading between 160 and 220 degrees. Some transmissions can run a safe normal transmission temp at temperatures a little higher than that range. But these numbers work as a general rule of thumb.

What is a high temperature for a transmission? ›

#1 Cause of Failure

The optimal temperature range for transmission fluid is 175 to 220 degrees. Above that, for every 20 degrees bad things happen, starting with formation of varnish at 240 degrees, followed by seals hardening, plates slipping, seals and clutches burn out, carbon is formed, and, ultimately, failure.

Which transmission line goes to the top of the radiator? ›

Generally the higher line on the radiator has fluid going INTO the transmission and the lower one goes back to the transmission, so the higher line has fluid coming out of it and the lower line sucks it back into the transmission.

How do you stop transmission fluid from leaking into radiator? ›

The only way to fix this is to flush all fluids out of your engine cooling system and replace them with fresh transmission fluid and anti-freeze. This can be a costly repair, so it's important to keep an eye on your car's fluid levels and make sure that the transmission fluid doesn't leak into the radiator.

How long does it take to change transmission cooler lines? ›

The timing will also vary depending on your vehicle model, year, and damage condition. On average, installing a new transmission cooler line on any auto vehicle takes a minimum of 1 & 1/2 hours to a maximum of 2 hours.

Top Articles
Latest Posts
Recommended Articles
Article information

Author: Tuan Roob DDS

Last Updated:

Views: 6427

Rating: 4.1 / 5 (62 voted)

Reviews: 85% of readers found this page helpful

Author information

Name: Tuan Roob DDS

Birthday: 1999-11-20

Address: Suite 592 642 Pfannerstill Island, South Keila, LA 74970-3076

Phone: +9617721773649

Job: Marketing Producer

Hobby: Skydiving, Flag Football, Knitting, Running, Lego building, Hunting, Juggling

Introduction: My name is Tuan Roob DDS, I am a friendly, good, energetic, faithful, fantastic, gentle, enchanting person who loves writing and wants to share my knowledge and understanding with you.