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Transmission systems are one of the most important parts of a vehicle. Without a transmission system, your car would not drive the way it does. It would be slow, with little to no power, cycling around a single gear.
Thus, keeping your gearbox in good working condition is critical to how well your car performs. Transmission fluid is used to keep all the moving parts of a gearbox lubricated and clean, making it an essential element to a hard-working gearbox.
With different styles of gearboxes, picking the right type of transmission fluid can be daunting; that’s why we’ve put together a list of the best transmission fluids currently on the market.
So let’s go through them and find the perfect transmission fluid for your car…
- Top 10 Best Transmission Fluids On The Market In 2021 Reviews
- 1 Red Line Manual Transmission Fluid – Most Versatile Manual Transmission Fluid
- 2 Red Line D4 Automatic Transmission Fluid – Most Versatile Automatic Transmission Fluid
- 3 Royal Purple Max High Performance Synthetic Automatic Transmission Fluid – Best Synthetic Transmission Fluid for Automatics
- 4 Castrol 03520C TRANSMAX DEX/MERC ATF – Most Versatile Transmission Fluid
- 5 Genuine Ford Fluid XT-M5-QS Full Synthetic Manual Transmission Fluid – Best Ford Transmission Fluid
- 6 Mobil 1 Synthetic Automatic Transmission Fluid – Best Premium Transmission Fluid
- 7 Pentosin ATF-1 Synthetic Automotive Transmission Fluid – Best Value for the Money Transmission Fluid
- 8 Toyota 00279-000T4 Automatic Transmission Fluid – Best Toyota Transmission Fluid
- 9 Lubegard 68115 Complete Universal CVT Fluid – Best CVT Transmission Fluid
- 10 Idemitsu ATF Type M Automatic Transmission Fluid – Best Type M Transmission Fluid
- Best Transmission Fluids Buying Guide
- Looking for more superb products to protect your engine?
- So, what are the Best Transmission Fluids?
Top 10 Best Transmission Fluids On The Market In 2021 Reviews
1 Red Line Manual Transmission Fluid – Most Versatile Manual Transmission Fluid
Red Line’s manual transmission fluid is a very versatile fluid that offers a bunch of benefits for your vehicle. Transmission fluids offer faster shifts, protection for your gears, and a better coefficient of friction from the gears.
This fluid works well regardless of the mileage of your vehicle and is popularly used with a large variety of vehicle manufacturers such as Mazda, Ford, VW, and many more.
Some like it hot…
Red Line’s fluid is better than most average transmission fluids with a higher temperature tolerance, which means it won’t split when things get hot. It also helps with cold shifts, especially in climates where temperatures drop below freezing.
The mixture is low in Sulphur, making it compatible with brass synchronizers.
- Offers smooth shifting.
- Protects gears.
- Works under higher temperatures than most other fluids.
2 Red Line D4 Automatic Transmission Fluid – Most Versatile Automatic Transmission Fluid
Just like Red Line’s manual transmission fluid, their automatic transmission fluid is top of the range. Offering excellent lubrication of the gears, with a smooth and superior feeling gear shift than any other fluid on the market.
Their transmission fluids not only work well under high temperatures but also provides excellent performance in colder climates. Where some liquids might split or seize, this fluid does no such thing.
Goes the distance…
This not only improves shifting but also protects your gears, which improves their lifespan, saving you a lot of money.
Considering all these benefits of Red Line’s transmission fluids, it’s more than worth the reasonable asking price.
- Works well under high or low temperatures.
- Increases lifespan of gears with superior protection.
- Smooth shifting.
- More expensive than other transmission fluids.
3 Royal Purple Max High Performance Synthetic Automatic Transmission Fluid – Best Synthetic Transmission Fluid for Automatics
Royal Purple offers an excellent synthetic transmission fluid for automatic vehicles that leaves most other synthetic fluids in the dust.
With a high film strength, this fluid is able to reduce wear and tear of everyday use whilst reducing the build-up of heat. This not only protects your gears but prolongs their lifespan.
Long lasting performance…
The liquid also lasts longer than other fluids because of its superb oxidation stability. Automatic transmissions tend to build up more heat than manual transmissions, which can cause the gears to wear out faster. By using Royal Purple’s high-performance transmission fluid, you protect the gears from this heat build-up and, in turn, protect them from wearing out quickly.
The fluid is also very versatile and compatible with most other ATF products, although it’s always best to flush the system and fill up with fresh transmission fluid.
Because of the improved oxidation stability, the fluid can be used for longer periods of time than most other transmission fluids, saving you money in the long run.
- Excellent performance.
- Long lasting.
- Versatile and compatible with most other ATF.
- Only for automatic vehicles.
4 Castrol 03520C TRANSMAX DEX/MERC ATF – Most Versatile Transmission Fluid
Castrol’s automatic transmission fluid is a versatile fluid that can be used with old trucks from the ’80s to more modern vehicles manufactured before 2005. That gives it the sort of versatility very few transmission fluids have.
Castrol is a very reputable brand with a lot of recognition in high-performance racing. That said, their products are usually reasonably priced, offering excellent products at affordable prices.
Reduces wear and tear…
This transmission fluid is very versatile and can even be used in your power steering pump instead of MERCON V. It not only lubricates the gears but offers added protection from heat. Therefore, keeping everything running smoothly while wear and tear are kept to a minimum.
Each gallon offers far superior protection and gear shifting at an affordable price.
- Improves friction for smoother gear shifts.
- Can be used with compatible power steering pumps.
- Container makes it hard to see the level of liquid left.
5 Genuine Ford Fluid XT-M5-QS Full Synthetic Manual Transmission Fluid – Best Ford Transmission Fluid
Buying OEM products are the best way to go about most thing automotive related, with that the next product in our Best Transmission Fluids review is Ford’s genuine manual transmission fluid. This ensures that you are getting a quality product that is made to work in perfect unison with your vehicle.
This fluid works best on IB5 transmissions, which are found on Ford vehicles between 1995 and 2011. It can also be used on older vehicles that require GL-3 or GL-4 oils for their transmission systems.
Hot or cold…
Ford’s transmission fluid works exceptionally well, no matter the temperature. The effectiveness of your transmission’s performance will greatly increase. This transmission fluid is recommended by Ford for all Ford vehicles, although it can also be used on other manual transmission vehicles.
This transmission liquid also works excellent with rear-wheel vehicles and all types of terrains. The synthetic manual transmission also lubricates the transmission system, keeping everything running smoothly and extends the lifespan of your gears.
- OEM quality and design.
- Protects gears.
- Versatile so can be used on many vehicles.
- OEM products are generally more expensive.
6 Mobil 1 Synthetic Automatic Transmission Fluid – Best Premium Transmission Fluid
Mobil 1 is a well-known brand among automotive enthusiasts and mechanics alike. Their products are made to high standards and offer better performance than most other products.
Mobil 1’s ATF provides excellent lubrication, resisting any oil deposits or breakdowns. The fluid has high viscosity stability, helping to protect it from any sort of thermal breakdowns that might happen during high temperatures or extreme pressure.
This fluid can be used in extreme, cold weather at temperatures down to -54 degrees Celsius. This makes it perfect to use no matter which climate you live in; whether it be scorching hot weather or freezing cold, this oil will get the job done no matter what.
The transmission fluid can be used on most vehicles from Ford to GM.
- Works well even under extreme conditions.
- Excellent protection.
- Lubricates gears well.
- Doesn’t work with DEXRON 4 vehicles.
7 Pentosin ATF-1 Synthetic Automotive Transmission Fluid – Best Value for the Money Transmission Fluid
This transmission fluid comes in a large 5L bottle at a very reasonable price. It’s another automatic transmission fluid designed for vehicles with electronically controlled converter clutch transmissions.
The liquid has been designed for lifetime use on automatic gearboxes. Pentosin manufactures this transmission fluid with the best available synthetic base oils, offering superior friction performance, keeping shifting smooth and your gears protected from break downs.
A superb option for sports and luxury cars…
Pentosin’s transmission fluid meets all requirements set by many luxury car dealers like Jaguar, BMW, and Audi. This sets it apart from a lot of its competition, making it the perfect partner for your luxury or sports car’s transmission.
The transmission fluid meets and even exceeds the requirements for Dexron III.
- Recommended by a number of luxury car dealers.
- Comes in a large 5L container.
- Meets Dexron III requirements.
- Some customers might not want a large 5L container.
8 Toyota 00279-000T4 Automatic Transmission Fluid – Best Toyota Transmission Fluid
As stated with the Ford transmission fluid, buying OEM products are usually better than buying aftermarket products, although they tend to cost more.
If you are driving a Toyota with an automatic transmission system, sticking with Toyota’s automatic transmission fluid is the best choice you can make.
A great option for slightly older vehicles…
This specific fluid is a T4 (Type 4) transmission fluid, specifically made for vehicles that were manufactured in the early 2000’s up to 2008. After these vehicles, most cars use WS fluids (world standard.) If you are unsure, check your vehicle’s manual for more guidance.
Other than that, what you can expect from this transmission fluid is a well performing and trustworthy product.
- OEM products are of guaranteed quality.
- Made for your vehicle brand specifically.
- More expensive than aftermarket products.
9 Lubegard 68115 Complete Universal CVT Fluid – Best CVT Transmission Fluid
CVT transmissions work differently from a standard automatic or manual gearbox. These systems don’t actually have “gears” in the same sense that the other transmission systems have. That means it will also need a different formula to protect the drums and band used for the CVT system.
Lubegard’s CVT fluid has been designed to keep friction between the belt and pulleys to a minimum while also protecting them from damage caused by overuse.
Stable and long lasting…
The formula is also very stable and does not oxidize, making it last much longer than standard transmission fluids. It’s resistant to cold and hot temperatures, which means it can be used in any climate or location.
If you own a vehicle that has a CVT system, Lubegard has the best transmission fluid on the market that will suit your needs.
- Made for CVT systems.
- Lasts longer than most other brands.
- Works well at all temperatures.
- For CVT transmissions only.
10 Idemitsu ATF Type M Automatic Transmission Fluid – Best Type M Transmission Fluid
Precisely engineered frictional characteristics guarantee smooth shifting and outstanding anti-shudder performance.
Idemitsu has designed this ATF with exceptional frictional characteristics, offering a superior, smooth shifting experience with first-rate anti-shudder performance.
Takes the heat…
It is oxidation resistant, making it stronger and less permeable to thermal breakdowns during cold or hot temperatures. The fluid does not seize up, keeping your transmission system free of any sludge or varnish deposits.
It also does not harm or harden any seals in your system, avoiding any leakage that may occur due to broken or worn out seals.
- Does not harm seals in the system.
- Works well in all temperatures.
- Only works with M3 and M5 vehicles.
Best Transmission Fluids Buying Guide
Before buying your next transmission fluid, it’s important to know about the different types of fluids and which are compatible with your vehicle.
In the automotive industry, there are two main types of transmissions, automatic and manual. Each one of these systems requires regular maintenance to work at peak performance. Proper servicing will lead to smoother gear shifts and keep your pockets safe from having to replace a whole gearbox.
Before we talk about the fluids in more detail, let’s look at the two most popular types of transmission fluids…
Automatic transmission fluids or, for short, ATF, will keep your gearbox free of rust whilst lubricating the gears for smoothing shifting. This helps keep the gears from overheating due to friction, as well as clearing out debris that may get caught in the gears.
Automatic transmissions require more regular services than manual transmissions due to the nature of the system, which means it will also need a more frequent change of transmission oil.
Manual transmissions, although much easier to keep in good condition, are also easier to buy oil for. Most transmission fluids will be compatible with a manual transmission; even some ATF’s will work with a manual transmission.
The most important thing to remember when buying for a manual transmission is to buy a product that will last a very long time. It needs to not oxidize quickly because manual transmissions don’t need their oil replaced as often as automatic transmission systems do.
So, what should you look out for in a transmission fluid?
Make sure that you know which transmission system you are buying for. This should be the obvious first step but can still often be overlooked.
After this, if your vehicles have an OEM transmission fluid, meaning it is made by the brand of car you drive, you should definitely pick that up. Original brand products are made with those specific vehicles in mind and will almost always offer better performance than aftermarket products.
Reading your vehicle’s manual will tell you the type of transmission fluid that is compatible with your vehicle.
Some transmission fluids have oxidant stabilizers, which help keep the fluid in a liquid state no matter what temperature. This is important to protect your transmission because if the liquid becomes too thick, it will lose its lubricating properties.
This could lead to extensive damage and high repair costs.
Finally, check the price of the product. But don’t make your choice only on the fluid’s cost. Purchasing the cheapest item available could cause you to experience issues with your vehicle’s transmission. Find one which will suit your vehicle the best but will also fit your budget.
Price shouldn’t be the first thing to consider, but it is important. But buying the most expensive product without needing its features would just be a waste of money. On the other end, buying the cheapest product might end up costing you more because of its sub-par performance leading to breakdowns or failures.
Buying the product that is made for your specific type of transmission system is the best bet. This is why we prefer OEM products because the quality and compatibility were fully considered when creating and manufacturing the product.
Looking for more superb products to protect your engine?
If so, then check out our Best Engine Antifreeze and Coolant, the Best Engine Air Filters, our Best Engine Flush Reviews, the Best Engine Enamel Paints, the Best Engine Degreaser, and the Best Oil Additives for Older Engines you can buy.
You may also be interested in our in-depth reviews of the Best Engine Hoist, the Best Synthetic Motor Oils, the Best Bicycle Engine Kits, the Best Two Stroke Oils, or the Best Car Battery Chargers currently on the market in 2021.
So, what are the Best Transmission Fluids?
Our top pick is…
There is one for manual and one for automatic. These fluids don’t just offer excellent lubrication but protect your transmission system from deteriorating over time. They are long-lasting but are also reasonably priced, which means you can protect your transmission system without breaking the bank.