If your car has an automatic transmission, then your automatic transmission fluid (ATF) is the lifeblood of the system. Clean and fresh ATF is critical to keeping your transmission running smoothly for thousands of miles. Just like engine oil changes, regular transmission fluid changes are important maintenance items that must be addressed. So, how do you know which transmission fluid you need to put into your car? Not all fluids are created equally, and using the wrong transmission fluid could be detrimental to your car’s transmission. Keep reading as we tell you the best transmission fluids and how to determine which one to use in your vehicle.
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Top 8 Best Transmission Fluids
You only want the best for your car, and the transmission fluid should be no different. Using poor-quality transmission fluid not only requires more frequent changes but could also lead to premature transmission failure. You should always use high-quality fluid in your transmission, and here are the eight best fluids out there.
Mobil1 produces some of the highest quality engine oil available, and their synthetic transmission fluid is also the best option out there. This Mobil1 fluid outperforms traditional transmission fluid, and its exceptional frictional properties will keep your transmission shifting smoothly for thousands of miles. You can use this fluid in a variety of vehicles as it meets both DEXRON, MERCON, and Chrysler requirements. If you want the best automatic transmission fluid available, this product from Mobil1 is the way to go.
If you are looking for a fluid that performs well but is more economical, then look no further than Amelie synthetic fluid. This universal fluid works in almost all vehicles, with the exception of those with a CVT transmission. This product contains advanced friction modifiers that will allow peak performance of your transmission for years to come. Amalie Universal Synthetic ATF is an excellent quality fluid at a great price.
Castrol is known for making great automotive fluids, and this automatic transmission fluid is designed specifically for the special requirements of imports. If you have a Toyota, Nissan, Honda, or other import, this fluid can help your transmission operate smoothly for many years. This fluid will stand up well to high temperatures, and it will continue to provide lubrication without breaking down for thousands of miles.
Valvoline is another trusted name in the automotive industry, and this transmission fluid provides excellent wear protection. If you have a high-mileage transmission, this fluid is also specially formulated to help recondition seals. Its excellent oxidation protection and anti-shudder protection keep your transmission shifting smoothly for the life of your vehicle. This fluid works in both domestic vehicles and imports, so you can use this fluid in almost any automatic transmission you might be driving.
This product from Valvoline is the first conventional transmission fluid on the list. It is designed specifically to meet DEX/MERC requirements, so you don’t want to use this in your import. However, if you have a DEX/MERC-compatible transmission, this is an excellent choice. Special additives help with the fluid flow at low temperatures while providing greater film protection at high temperatures.
Royal Purple is known for making products specifically for high-performance applications. While this fluid works great in those applications, it is also an excellent choice for passenger vehicles. Royal Purple Max is proven to help you get the most horsepower out of your engine while also maximizing your fuel economy. This product has excellent torque hold capability, so you won’t have to worry about any clutch slippage – even under full throttle. You can use this fluid in hybrid vehicles, so it will work in a wide variety of applications.
If you have an automatic transmission, then you should pick one of the other fluids on the list. This Red Line product is specifically for manual transmissions, but it is the best manual transmission fluid and gear oil out there. This fluid is designed to allow for quicker shifts and to extend the life of your synchros. It even works with brass synchros as well! Great for cold weather shifting, and it works great in both high-mileage transmissions and newer transmissions.
This product is specifically for DEXRON applications, and it is backward compatible all the way to DEXRON III. ACDelco makes OEM fluid and equipment for almost all vehicles from General Motors, and this fluid is an excellent choice if you own one of these vehicles. Your manufacturer generally knows your vehicle best, so why trust your transmission to anyone else? This product provides excellent oxidation protection, outstanding friction durability, and superior foam control, and you’ll be driving smoothly for thousands of miles when you use this fluid.
Types Of Automatic Transmission Fluid (ATF)
By now, you probably realize that there are several different types of automatic transmission fluids available. Some fluids can be used in multiple applications, while others are specifically designed for only one transmission type. Here are the basics of the different transmission fluid types.
— Natural vs. Synthetic Fluid
Just like engine oil, natural transmission fluid has natural base oils with additives. Synthetic fluid uses synthetic base oils that have been chemically altered. This chemical process also alters other qualities of the fluid, and it makes synthetic fluid outperform natural fluid in most lubrication and other tests.
— Type A
Type A transmission fluid was used in older vehicles, dating all the way back to the 1950s. However, Type A fluid started to be phased out as modern cars began to require more specific fluid in their transmissions. Type A fluid was known for breaking down at high temperatures, and it cannot withstand the demands of modern transmissions. If you have a classic car, you might use Type A fluid. However, it can sometimes be difficult to find today.
— Type F
Type F transmission fluid is specially designed for use in Ford vehicles, and it is approved by Ford Motor Company. This fluid is typically used in older Ford cars, as most newer Fords require Mercon fluid. Type F fluid can also be used in some imports, although you should check your owner’s manual for specific details.
Dexron is a special type of automatic transmission fluid that is designed and created by General Motors. There are a few different generations of Dexron fluid, but the latest is Dexron VI. This fluid is a synthetic-based fluid that is designed to meet the high demands of modern transmissions. If you have a GM vehicle produced in the last five years or so, you will probably need to use Dexron VI fluid in it.
Just like Dexron was developed by General Motors, Mercon fluid must meet a set of technical specs created by Ford Motor Company. This is the type of fluid that should be used in Ford, Lincoln, and Mercury vehicles. The latest iteration, Mercon V, has a high viscosity index and additives that help with shifting at both low and high temperatures. If you own a Ford, you will want to look for a Mercon fluid.
Choosing The Right Transmission Fluid For Your Vehicle
Are you wondering, “What kind of transmission fluid do I need?” You might think that any transmission fluid will work in your vehicle, but that is not correct! Most vehicles require a specific type of fluid, and using the wrong kind of fluid can damage your transmission. For instance, Ford vehicles typically require MERCON fluid. Cars made by General Motors usually require DEXRON fluid. Even between these types, there are different versions of the fluid, such as MERCON III or DEXRON VI.
The best way to determine the type of fluid to use in your transmission is to consult your owner’s manual. The manual should specify the type of transmission fluid required by your vehicle, and you should always use the type specified in the manual. In an emergency situation, you may be able to use a generic transmission fluid. However, make sure that the fluid you use is compatible with the fluid already in your vehicle. You should be especially careful if your vehicle has a CVT transmission. A CVT, or continuously variable transmission, sometimes requires special fluid, and not just any automatic transmission fluid will work.
Just like engine oil, you will also find both conventional and synthetic transmission fluids. Regular transmission fluid is made of organic base oils, while synthetic fluid is made from chemically altered base oils. The synthetic fluid typically provides better lubrication and withstands extreme temperatures better than regular ATF. Some newer vehicles require synthetic fluid, although you might choose to use a synthetic fluid in your older vehicle as well. Just make sure that the fluid meets all the requirements specified in your owner’s manual.
Important Transmission Fluid Additives
There are a few types of additives that you should be aware of, and we’ll cover the basics here. First, you will find additives already in many transmission fluids that you purchase. The specific additives contained in these fluids are somewhat of a mystery, as most major brands use their own proprietary blend of additives. However, there are a couple of things that these additives are designed to do.
First, most fluid contains an additive that helps condition seals inside the transmission. This helps prevent leaks and ensures that all your fluid stays inside the transmission. Next, most fluids also contain additives that help with viscosity and lubrication. This prevents excess wear and tear on your transmission because less friction is generated between the moving parts. At the same time, less friction leads to lower temperatures in the transmission. Heat is the #1 killer of transmissions, so lower temperatures will almost always lead to a longer lifespan. You probably already know that the cost to repair a transmission is expensive, so you want to get the longest life possible from yours.
Not only does most transmission fluid already have additives in it, but there are many standalone additives that you can purchase and put into your transmission. Some are meant to fix specific problems. For example, you may choose to put a friction modifier additive in the transmission to fix shuddering or shifting problems. You can also purchase specific additives to stop leaks or help a slipping transmission. Lucas makes wonderful automotive products, and their Lucas Transmission Fix product can work wonders for older transmissions.
Some additives are also designed specifically for high-mileage transmissions. These products help clean sludge from the transmission, and they also help restore the seals and bands inside the transmission. You can also find additives for your manual transmission, but these products are typically different from what you will find for automatic transmissions because they operate so differently.
Why Is Fresh Transmission Fluid Important?
Just like your engine needs fresh engine oil, your transmission also needs fresh transmission fluid to operate properly. Transmission fluid is important for a number of reasons, and here are some of the most important functions of fresh transmission fluid.
First, transmission fluid keeps the internal parts of the transmission lubricated. The bands, gears, and other moving parts in the transmission are metal, and these parts must stay lubricated as they move against each other. Transmission fluid begins to break down and lose its lubricating ability over time. This is one of the biggest reasons why fresh fluid is so important.
Another reason fresh fluid is important is that the fluid becomes dirty over time. You will likely even get small metal shavings or fragments in the fluid as the transmission operates for thousands of miles. When you change the transmission fluid, this debris gets drained out with the old fluid. Leaving the old fluid and debris in the transmission can cause big problems.
Finally, we have already mentioned that heat kills transmissions. Transmission fluid is critical to removing heat from the gearbox – just like motor oil helps remove heat from your engine. Old transmission fluid is not able to remove as much heat as new fluid. Just like old fluid loses its lubricating ability, it also loses its ability to help with temperature control. This is another extremely important reason you should change your transmission fluid regularly and keep fresh fluid in your automatic transmission.
How Often To Change Your Transmission Fluid
Now that you know the importance of fresh transmission fluid, how often should you change the fluid in your vehicle’s transmission? First, you should always keep a regular check on the transmission fluid level. If the level gets low, you need to add fluid immediately. You should also repair any leaks in the system, as your transmission fluid should not get low unless there is a leak. If you notice that the fluid on the dipstick is brown or foaming, it should be changed immediately. Fresh fluid should appear reddish or pink in color, and there should be no burnt smell to the fluid.
When it comes to transmission fluid changes, most mechanics recommend changing your transmission fluid every 50,000 to 60,000 miles. Some vehicles may require less frequent changes, but you should always follow your manufacturer’s recommendation when determining when to change the transmission fluid in your car. Refer to your owner’s manual for the recommendation for your car.
You might also need to decide between a transmission fluid flush and a transmission fluid change. A fluid change usually involves dropping the transmission pan and allowing the old fluid to drain from the vehicle. The pan is reattached, and new fluid is poured into the transmission. During a fluid change, some old fluid remains inside the torque converter, so roughly 75% of the fluid actually gets changed.
A fluid flush, on the other hand, involves flushing the old fluid from the system and replacing it with new fluid. Some mechanics recommend that a flush only be performed on newer vehicles, while older transmissions should stick to a regular fluid change. The reason for this is that some people believe that a fluid flush may dislodge debris in older transmissions and cause problems. Newer transmissions should not have any debris, and a flush should not damage them. You should talk to your mechanic to determine which one is right for your car.
The Bottom Line
Picking the right transmission fluid for your car is as important as picking the right engine oil. Make sure that you consult your owner’s manual to determine the specs for which type of transmission oil is required in your transmission. Just like synthetic oil, there is also synthetic ATF available today. All of the transmission fluids on this list provide excellent wear protection, and they contain special additives that help prevent leaks and fluid breakdown. You can’t go wrong with any of the fluid on this list, but make sure you use the appropriate one for your application.
Frequently Asked Questions
Is it better to use synthetic transmission fluid?
Yes, most mechanics agree that synthetic fluid is better than conventional transmission fluid. Synthetic fluid provides better lubrication than traditional fluid, and synthetic fluid lasts longer. Synthetic fluid is specifically designed to withstand breakdown, and it continues to perform well for thousands of miles, even under extreme temperatures. For these reasons, synthetic fluid is generally preferred, especially in high-performance applications.
What is the best transmission fluid for high mileage?
Castrol Transmax High Mileage transmission fluid is one of the best fluids for high-mileage transmissions. This Castrol transmission fluid contains special additives to help with smoother shifts and less wear on older transmissions. Additionally, it contains special seal conditioners that can help stop and prevent leaks by restoring the seals and gaskets to like-new condition. Special corrosion inhibitors prevent the oxidation of planetary gears and other moving parts. The fluid meets both DEXRON and MERCON requirements, so you can use this fluid in many different types of cars, including Ford, Mercury, Chevrolet, Nissan, Toyota, and others.
Can you use automatic transmission fluid in a car with a manual transmission?
In most cases, the answer is yes. However, there are some caveats. It is typically not advisable to use automatic transmission fluid in manual transmissions due to the different needs of each type of transmission. You should remember that automatic transmission fluid acts as both a lubricant and a hydraulic fluid. Manual transmissions, however, only need a lubricant. Some manufacturers suggest using ATF as the lubricant in their manual transmissions, but you should always refer to your owner’s manual to determine the type of fluid needed in your vehicle.
Does it matter which brand of transmission fluid you use?
Generally, no, the brand of fluid you use does not matter that much. The one thing that really matters is the type of fluid you use. For example, if you drive a Ford that requires MERCON III fluid, then you must use a fluid that meets the MERCON requirements. Using a fluid that does not meet the requirements of your transmission will cause problems and potential damage to your transmission. There are many different brands available that meet the requirements of modern cars, although some brands tend to be better than others. If you want the best transmission fluid available, then use one of the fluids from the list in this article.