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10 Best Transmission Additives in 2022 – Reviews & Top Picks

man refilling fluid on car engine_TimMossholder_Unsplash

man refilling fluid on car engine_TimMossholder_Unsplash

Transmission additives are advertised as fixing a variety of transmission problems. You simply add them to your transmission fluid, and you may notice a reduction in a variety of different issues, such as erratic shifting, leaks, and similar problems.

However, not all transmission additives are the same. Some do not actually do much at all, and others can even make problems worse. Therefore, it is vital that you choose only high-quality transmission additives. Otherwise, you can make everything much worse!

Below, we’ve reviewed some of the best transmission fluid additives on the market. Many of these have great reviews and may actually help some of your problems.

car and road divider

A Quick Comparison of Our Winners (2022)

Rating Image Product Details
Best Overall
Prolong Super Lubricants PSL15000 Transmission Treatment Prolong Super Lubricants PSL15000 Transmission Treatment
  • Chemically bonds to metal
  • Improves gear changes
  • Inexpensive
  • Best Value
    Second place
    Lucas LUC10009 Transmission Fix Lucas LUC10009 Transmission Fix
  • Solvent-free formula
  • Works for a variety of problems
  • Inexpensive
  • Premium Choice
    Third place
    Lubegard 19610 Dr. Tanny Instant Shudder Fix Lubegard 19610 Dr. Tanny Instant Shudder Fix
  • Concentrated
  • Designed specifically to eliminate shudder
  • Reduces wear
  • Hot Shot’s Secret Hot Shot’s Secret
  • Suitable for use in most engines
  • Reduces operating temperature
  • Lubricates
  • LUCAS Oil 10441 Automatic Transmission Fluid Condition LUCAS Oil 10441 Automatic Transmission Fluid Condition
  • Extends life of transmission fluid
  • Prevents common transmission problems
  • Can be used in both new and old transmissions
  • The 10 Best Transmission Additives

    1. Prolong Super Lubricants PSL15000 Transmission Treatment – Best Overall

    Prolong Super Lubricants PSL15000 Transmission Treatment

    Size: 8 oz

    Out of all the transmission fluids on the market, the Prolong Super Lubricants PSL15000 Transmission Treatment is easily the best overall transmission additive. While many transmission additives do not actually do anything, this one does. It is easy to see why it is one of the most popular options.

    It works by producing molecules that interact with the surface of metals. The molecules coat the metal and work as a protective shield. Overall, this can help lower the heat and friction in the transmission system. This may help a variety of different transmission problems.

    In the end, many customers noticed improved gear changes. We recommend this lubricant for a variety of different cars, including everyday vehicles and weekend drivers. A single bottle goes a long way and can completely treat the whole system. It lasts a while, as well, since it chemically bonds to the metal.

    With that said, this only works for CVT transmissions, so it is not useable on all cars.

    • Chemically bonds to metal
    • Improves gear changes
    • Inexpensive
    • Lasts for an extended period
    • Only one bottle needed
    • Only works on CVT transmissions

    2. Lucas LUC10009 Transmission Fix – Best Value

    Lucas LUC10009 Transmission Fix

    Size: 24 oz

    For those looking for a budget option, we highly recommend the Lucas LUC10009 Transmission Fix. Not only is this transmission additive quite inexpensive, but it is also very good for slippage. It forms a film on the inside of the transmission that helps protect bands and prevent the system from overheating. Therefore, it can prevent slippage and even cure slippage problems.

    It is a solvent-free formula that does not foam. On top of producing a film, it helps seal leaks and lowers the operating temperature of the fluid. If you have older transmission fluid, this formula can also help improve its quality. You may not need to change your transmission fluid as often, though this is not necessarily recommended.

    This product is relatively new compared to the others we’ve mentioned, but it has seemed to work well thus far. It can work on a variety of transmission problems, including leaks and hard shifting. Therefore, it is one of the better options on the market for most transmission problems.

    With that said, this is not a cure for all transmission problems. It may not work as well for serious problems, as it is not particularly heavy-duty. Still, this is easily the best transmission additive for the money.

    • Solvent-free formula
    • Works for a variety of problems
    • Inexpensive
    • Produces a film of protection
    • Doesn’t work for extremely heavy-duty problems

    3. Lubegard 19610 Dr. Tanny Instant Shudder Fix – Premium Choice

    Lubegard 19610 Dr. Tanny Instant Shudder Fix

    Size: 4 oz

    Lubegard 19610 Dr. Tanny Instant Shudder Fix is a great option for preventing and fixing transmission shudders. It is specifically designed for this purpose and does a very good job at improving overall transmission performance. Customers tend to be rather surprised by how well this transmission additive works. However, it is also more expensive than other options, so it is not for someone looking for a budget option.

    We liked that this concentrated formula is designed specifically to prevent transmission shudders. Therefore, if your transmission has this problem, this is probably your best bet to fix it.

    This formula also prevents wear by as much as four times. Therefore, you may want to use it even if your transmission is currently fine as it can prevent problems from occurring in the future.

    While this formula is designed for most cars, it is not suitable for CVT applications.

    • Concentrated
    • Designed specifically to eliminate shudder
    • Reduces wear
    • Can improve overall transmission performance
    • Expensive
    • Not for CVT applications

    4. Hot Shot’s Secret

    Hot Shot’s Secret

    Size: 32 oz

    Hot Shot’s Secret is designed to clean your transmission, which can often reduce and eliminate common transmission problems. It dissolves gum and varnish that may form in your transmission over time. You can also use it to prevent these materials from forming inside your transmission, to begin with. It is suitable for use in both gas and diesel automatic engines, so you should be able to use it in most cars.

    The main purpose of this transmission additive is to reduce the operating temperature of your transmission. This effect can limit many common transmission problems. However, this transmission additive also works as a hydraulic fluid and lubricant. Therefore, it can do many jobs at once.

    This formula will instantly attach itself to your car’s metal parts, which helps prevent deposits and grinding. Over time, this can reduce transmission wear and even reverse some wear that has already occurred.

    • Suitable for use in most engines
    • Reduces operating temperature
    • Lubricates
    • Begins working instantly
    • Doesn’t always make a huge difference

    5. LUCAS Oil 10441 Automatic Transmission Fluid Condition

    LUCAS Oil 10441 Automatic Transmission Fluid Condition

    Size: 20 oz

    The LUCAS Oil 10441 Automatic Transmission Fluid Condition may not readily solve any of the problems you currently have. However, it may help prevent future problems. As the name suggests, this conditioner is only for automatic transmissions, which does limit its usability. It can prevent slippage, leaks, and general wear inside the transmission, but it is not actually designed to correct any of these problems once they start occurring.

    Furthermore, this liquid can extend the life of your transmission fluid, allowing you to extend the time between changes. If you are a bit late on a change, then you typically don’t have to worry about anything if you use this transmission additive.

    You can use it on both new and old transmissions. However, as we have stated, it is not going to fix any existing problems—just prevent new ones.

    • Extends life of transmission fluid
    • Prevents common transmission problems
    • Can be used in both new and old transmissions
    • Affordable
    • Doesn’t correct current problems
    • Only for automatic transmissions

    6. Lubegard 60902 Automatic Transmission Fluid Protectant

    Lubegard 60902 Automatic Transmission Fluid Protectant

    Size: 10 oz

    If you’re looking for a protective additive, you may want to consider Lubegard 60902 Automatic Transmission Fluid Protectant. This additive is specifically designed to prevent overheating by reducing the overall operating temperature of the transmission. When used before problems erupt, this can prevent all sorts of common transmission problems.

    Furthermore, this additive will eliminate foaming transmission fluid, as well as prevent oxidation and reduce wear. Therefore, it may help your transmission last longer and prevent a variety of common problems. We recommend it for use in all cars with automatic transmissions, though newer cars are more likely to get something out of it.

    Because this fluid helps raise the operating conditions of the transmission fluid, it can help the transmission fluid last longer. Therefore, it may help you save a bit of money over time.

    With that said, this transmission fluid is a bit expensive, and the bottle is very small. Therefore, you’re going to spend more in the long run. It is also only protective and doesn’t actually cure any problems you may already be having.

    • Protects transmission from wear and tear
    • Raises operating stability of transmission fluid
    • Easy to apply
    • Reduces operating temperature
    • Expensive
    • Small bottle

    7. Cerma Automatic Transmission Treatment

    Cerma Automatic Transmission Treatment

    Size: 2 oz

    The Cerma Automatic Transmission Treatment comes in a much smaller bottle than most others out there. However, the bottle is enough for a complete treatment. You’ll just have to purchase a new bottle every time you need to retreat (which can get quite expensive). This transmission additive is not cheap, however, it is one of the few that is actually designed to correct some common problems.

    For instance, it is designed to be used after your transmission starts acting up. You can use it to stop slippage and rough slipping, for instance. It works by lowering the operating temperature of the transmission fluid and sealing leaks. It can also reduce friction in the transmission, which helps eliminate many problems.

    It only works in automatic transmissions, though. Plus, there are several reports that it doesn’t cure serious problems, though many customers did see a small improvement.

    • Fixes common transmission problems
    • Reduces friction to prevent future wear
    • Easy application
    • Doesn’t cure serious problems
    • Expensive

    8. XADO Revitalizant EX120 Conditioner

    XADO Revitalizant EX120 Conditioner

    Size: 8 ml

    Like most additives on this list, this conditioner is only designed for automatic transmissions. However, the same company does make an alternative option for manual transmissions. The size of the bottle is very small. In fact, it doesn’t actually come in a bottle at all. Instead, it comes in a small syringe.

    This additive is advertised to help “rebuild” metal parts inside your transmission, which may help eliminate current problems. It also works as a protectant by preventing wear, reducing the chance of problems in the future. It prevents friction and reduces the operating temperature of your car’s transmission.

    You can use it for most automatic transmissions, including CVT and Tiptronic.

    However, there are many reports of this conditioner simply not working very well. Furthermore, it has an average price, so we can’t group it with budget options, either. For this reason, it has a low value when you compare its effectiveness and price.

    • For all automatic transmissions
    • Prevents and cures transmission problems
    • Easy application with no measuring needed
    • Only one treatment per package
    • Low value for money

    9. BG ATC Plus

    BG ATC Plus

    Size: 11 oz

    The BG ATC Plus is mostly designed to enhance your transmission fluid. It works on both new and old transmission fluid to improve its functioning, which can in turn help protect your transmission. It increases oxidation stability, prolonging the life of your transmission and saving you a bit of money.

    Furthermore, it can prevent leaks by keeping seals soft and pliable. It may even be able to fix leaks that are caused by hardening seals, though this is debatable. In some cases, this additive was found to prevent the formation of sludge and other deposits, which can prevent all sorts of transmission problems.

    With that said, this additive will not help eliminate fluid changes or anything of that sort. It also can’t work miracles on older cars. In fact, we really only recommend it as a regular additive on new cars, along with regular transmission fluid changes.

    • Can prevent leaks
    • Increases oxidative stability
    • Affordable
    • A bit harder to use
    • Best for newer cars

    10. Bar’s Leaks 1416 Super Transmission Fix

    Bar’s Leaks 1416 Super Transmission Fix

    Size: 16.9 oz

    According to the advertising, Bar’s Leaks 1416 Super Transmission Fix can correct certain transmission problems. For instance, this fluid may reduce noise and renew worn seals. Many customers do report that it seems to work on minor problems. However, there were just as many people reporting that it didn’t work so this seems to be a lower-quality additive (which makes sense considering the relatively low price).

    This fluid does come in a relatively large bottle—at least compared to many of the options on this list. However, you also need a lot of liquid to treat the average transmission, so don’t let the bigger size make you think you’re getting a deal. Sure, you’re getting more liquid, but you have to use more during fluid changes.

    Based on reports by those with much older cars, this transmission additive seems to work best on newer cars. In fact, most people with transmissions with over 100k miles did not notice any difference.

    • Can fix minor transmission problems
    • Affordable
    • Requires a lot of fluid per treatment
    • Works best on new cars

    car and road divider

    Buyer’s Guide: How to Select the Best Transmission Additives

    It can be challenging to tell different transmission additives apart from each other on the shelf. Often, they have very similar advertising that proclaims that each additive can prevent or cure a wide range of transmission problems.

    However, there are some significant differences between these additives. They are not all interchangeable, despite the similar advertising. When choosing an option for your car, keep these things in mind.


    Most transmission additives are either designed for automatic or manual transmissions and you’ll need to choose the option that matches your car. While picking up the incorrect additive won’t necessarily damage your car, it could. You don’t want to add an incompatible additive to your vehicle. At the very least, you’d need to do a complete fluid change after this mistake, which can be costly.

    A manual transmission creates a lot of heat and friction. To withstand this, transmission fluid additives for manual transmissions often have a high viscosity and are designed to work under extreme heat.

    On the other hand, automatic transmissions are usually smaller and may have more moving parts. Usually, the additives designed to work for automatic transmissions have anti-foaming qualities and a low viscosity.

    Fluid Type

    There are two main types of transmission fluids: synthetic and natural. Synthetic is by far the most common. However, you should still check to see what type of fluid your car has before purchasing an additive. Many additives can only be used with certain fluid types, and things can get quite messy if you use the wrong additive.

    Usually, the compatibility list will be located in the instructions on the back of the additive container.


    Not all additives are made the same, as you might guess. Some are extremely high-quality and can help reduce a number of problems, while others may not work at all. Usually, the big-name brands have the best quality additives, as they wouldn’t be in business otherwise. However, these are usually also more expensive.

    When in doubt, it is best to look at reviews like ours. Usually, using the additive is the only way to determine how effective it is. If you just want to get the right product the first time, we recommend selecting from our reviews above.


    filling up car engine with new transmission fluid
    Image Credit: Oteera, Shutterstock

    Not all additives are designed to do the same thing. Many lower the operating temperature of the transmission fluid, but beyond that, it varies widely. You’ll need to consider the problems you’re having and find a transmission additive that can fix those problems.

    Also, many are designed either to prevent problems or solve those that already exist. If you have a newer car, a preventative transmission is likely what you need. However, these may not work very well if your car is older and already experiencing problems.

    Applications Per Package

    Usually, when you see a large package you assume that it contains a lot of applications. However, this is not necessarily true. Different additives require more liquid per application. This varies a lot. Some need whole liters per application, while others need a fraction of that.

    When determining whether or not you’re getting a good deal, look at how much fluid you need per application. If you’re purchasing a bottle with two applications for an affordable price, you’re getting a pretty good deal.

    Compare the price of additives based on the number of applications in the bottle and not based solely on the size of the package. In this case, a price-per-ounce isn’t a very effective measuring stick.


    Do transmission additives actually work?

    Yes, to an extent. No additive can magically fix serious problems in your transmission. This isn’t what they are designed for. If you’re expecting them to completely fix your transmission, you’re going to be disappointed. Instead, they simply work to optimize your transmission fluid.

    A car that regularly sees a transmission additive will likely have less wear and fewer transmission problems. If your car already has transmission problems, there isn’t a lot that an additive can do.

    These additives work far better when you use them throughout your car’s lifespan. Starting when your car is older may do a little bit, but much of the wear has already occurred.

    Should I use a transmission additive?

    A transmission additive is a bit like insurance. No one can tell you whether or not you’re going to use your insurance plan. However, if you do need your insurance plan, you’ll thank yourself for getting it.

    Transmission additives can prevent transmission problems. However, no one can tell you if your car will end up with a transmission problem later or if it’ll be decommissioned before that ever happens. With that said, if you don’t use transmission additives and your car ends up with a transmission problem, you’ll likely end up regretting your decision.

    When they do their job, you’ll never know whether you actually needed a transmission additive or not. For this reason, many people mistakenly skip on them to save some money. Based on how expensive transmission problems can be, paying a little extra for a transmission additive is worth it in our book.

    car and road divider


    For most cars, we recommend the Prolong Super Lubricants PSL15000 Transmission Treatment. It is not terribly expensive, and it can prevent a variety of transmission problems. It chemically bonds to metal, which also means that it lasts longer than most other additives.

    However, for those looking for the absolute cheapest option, we recommend Lucas LUC10009 Transmission Fix. It comes with more applications per bottle and produces a protective film, which helps prevent wear and tear.

    We highly recommend choosing a transmission additive off of our list above, as they have all been checked for effectiveness. Hopefully, one of our reviews stood out to you and proves to be what you need.

    Featured Image Credit: Tim Mossholder, Unsplash

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