Experiencing a slipping transmission can be a nerve-wracking and costly concern for any driver. Before you start worrying about a major repair bill, a specialized transmission additive could be the effective and affordable solution you need. These formulas are engineered to address common issues like hard shifting, shuddering, and slippage by improving the fluid’s properties and protecting internal components.
This guide provides a detailed look at ten of the most reliable and well-regarded additives on the market. Whether your goal is to restore smooth shifting, eliminate a persistent shudder, or simply extend the life of your transmission, you can find a product here that fits your specific vehicle and situation.
Our Top Picks for Transmission Additives
- Hot Shot’s Secret Shift Restore Automatic Transmission Additive
- XADO AMC Automatic Transmission Additive Hard Shifting Instant Shudder Fixx
- zMAX Transmission Formula 2 Pk – Automatic and Manual Transmission Fluid Additive
- MotorPower Care Automatic Transmission Flush Cleaner Stop Slipping and Hesitation
- Lucas Oil 10009 Transmission Fix – 24 Ounce
- Lubegard 19610 Instant Shudder Fix
- Prolong Super Lubricants PSL15000 Transmission Treatment – 8 oz.
- BG ATC Plus
- Valvoline MaxLife Multi-Vehicle ATF Full Synthetic Automatic Transmission Fluid
- ATP Automotive AT-205 Re-Seal
Hot Shot’s Secret Shift Restore Automatic Transmission Additive
Hot Shot’s Secret Shift Restore is a powerful additive designed for both automatic and CVT transmissions. It works by targeting the root causes of slipping and rough performance. Its advanced formula is engineered to reduce the operating temperature of your transmission, which is a key factor in preserving the life of the fluid and internal parts.
By significantly reducing the coefficient of friction, this product helps restore proper clutch engagement and eliminates slippation. This leads to smoother, more confident gear changes and can help bring a struggling transmission back to proper operating condition.
XADO AMC Automatic Transmission Additive Hard Shifting Instant Shudder Fixx
The XADO AMC Automatic Transmission Additive uses a unique atomic metal conditioner to provide a rapid fix for transmission slips and shudders. This product is known for its ability to revitalize worn surfaces within the transmission, leading to enhanced responsiveness and smoother shifting almost immediately after application.
Beyond just fixing current issues, the formula works to fortify metal surfaces, which enhances operational reliability and reduces noise. By preventing shifting and sticking problems, it contributes to the overall longevity of your transmission, making it a strong preventative maintenance choice as well.
zMAX Transmission Formula 2 Pk
zMAX Transmission Formula is a micro-lubrication treatment suitable for both automatic and manual transmissions. Its technology soaks into metal surfaces to improve lubrication, which directly reduces gear wear and prevents varnish buildup. This process also helps keep seals supple, which can prevent leaks and improve shifting quality.
Adding this formula to your transmission fluid can improve overall efficiency by reducing slippage and rough shifting. It is designed to bring back smooth gear changes and is safe to use every time you perform a transmission fluid change, without voiding manufacturer warranties.
MotorPower Care Automatic Transmission Flush Cleaner
MotorPower Care offers a flush cleaner that is compatible with all vehicles featuring automatic or CVT transmissions. This product is specifically formulated to clean and dissolve contamination that can build up within the transmission system, particularly on critical components like solenoids.
By effectively cleaning out varnish and sludge, it helps to stop slipping and hesitation. A key benefit is that it lubricates the system while it works, ensuring that the cleaning process does not cause any damage and contributes to smoother operation.
Lucas Oil 10009 Transmission Fix
Lucas Oil Transmission Fix is a long-trusted solution for slipping transmissions. Its non-petroleum, non-solvent formula is safe for transmission seals and works to stop slippage by conditioning the clutch material. A major advantage is its ease of use; it can be added directly to your existing transmission fluid without the need for draining.
This additive also helps lower operating temperatures and prevents fluid from foaming, which are both critical for maintaining transmission health. By improving the fluid’s viscosity and sealing properties, it can often postpone the need for costly transmission work.
Lubegard 19610 Instant Shudder Fix
Lubegard Instant Shudder Fix is the original product specifically created to eliminate torque converter shudder. This common issue, which feels like a rapid vibration during light acceleration, can be both annoying and damaging if left untreated.
This concentrated formula works instantly to restore proper friction characteristics in the transmission fluid. It is also proven to provide up to four times less wear than regular automatic transmission fluid, offering both an immediate fix and enhanced long-term protection for your transmission.
Prolong Super Lubricants PSL15000 Transmission Treatment
Prolong Super Lubricants Transmission Treatment utilizes a sophisticated anti-friction metal treatment technology. Its engineering is designed to treat metal surfaces through a molecular and chemical process that goes beyond simple lubrication.
The active molecules in the formula interact with metal surfaces, creating a protective layer that chemically bonds to the metal. This layer is highly effective at reducing the damaging friction and heat that lead to transmission wear and component failure.
BG ATC Plus
BG ATC Plus is a professional-grade additive that enhances the properties of both new and used automatic transmission fluid. It is particularly effective at improving the fluid’s oxidation stability, which is the primary reason transmission fluid breaks down over time.
By slowing oxidation, this product prolongs the effective life of the fluid and, consequently, the transmission itself. It also includes seal conditioners that work to prevent leaks by keeping seals soft and pliable, addressing two major transmission concerns with one product.
Valvoline MaxLife Multi-Vehicle ATF Full Synthetic Automatic Transmission Fluid
While not an additive in the traditional sense, Valvoline MaxLife ATF is a full synthetic fluid designed for use in over 95% of vehicles, including most CVTs. It serves as an excellent solution for a complete fluid change when dealing with slipping or other performance issues.
Its formulation includes high-performance conditioning agents that prolong seal elasticity to prevent leaks. The advanced anti-wear technology also provides improved durability and can help extend the overall life of your transmission, helping you avoid costly repairs.
ATP Automotive AT-205 Re-Seal
ATP Automotive AT-205 Re-Seal takes a unique approach by specifically targeting hardened and shrunken transmission seals. Many transmission issues, including slipping, can be traced back to leaks that cause low fluid levels. This product works to recondition and restore the original size and flexibility of rubber seals.
By making seals soft and pliable again, AT-205 can stop leaks and help maintain proper fluid pressure, which is essential for correct clutch engagement and gear shifting. It is a straightforward solution for addressing slippage caused by minor seal leaks.
Buying Guide: What to Look For in the Best Additives for Slipping Transmissions
When my own car’s transmission started hesitating between gears, I knew I had a problem. Before panicking about a multi-thousand dollar rebuild, I looked into transmission additives. They aren’t a magic cure-all, but the right one can buy you significant time and improve performance. The key is knowing what to look for in the best additives for slipping transmissions.
First, you need to understand what the additive is designed to do. Most of them work by conditioning the seals. Over time, the rubber seals inside your transmission can harden and shrink, leading to fluid leaks and a loss of hydraulic pressure. This pressure is what makes the clutch packs engage, so when it’s low, you get slipping. A good seal conditioner will re-swell and soften these seals, restoring that crucial pressure. Look for products that specifically mention seal conditioning or reconditioning.
Next, consider your transmission type. Is your vehicle an older model with a traditional automatic, or a newer one with a sophisticated CVT or dual-clutch system? This is a huge deal. Using a standard automatic transmission additive in a CVT can actually destroy it. CVTs have specific, often synthetic, fluids and require additives formulated for their unique metal-on-metal belt and pulley system. Always, always check your owner’s manual and the product bottle to ensure compatibility. When in doubt, err on the side of caution and don’t use it.
You should also think about the existing condition of your transmission fluid. Pull the dipstick (when the engine is warm and running, on a level surface). If the fluid is dark brown or black, smells burnt, or has visible particles, an additive is likely a temporary band-aid at best. The damage may already be too advanced. Additives work best with fluid that is still in decent condition—pink or red—and are used to address a recent, minor slip or shudder. If your fluid is burnt, a fluid and filter change is a much better first step, and you can add the treatment to the new fluid.
Finally, look at the product’s claims and reputation. I avoid anything that promises a “complete fix” for a “failing transmission.” That’s just not realistic. Instead, I look for products from reputable brands that have positive, long-term reviews from users with similar vehicle issues. A product that helps with rough shifting, delayed engagement, and minor slipping is being honest about its capabilities. Remember, these are maintenance aids, not resurrection potions. Using them can be a smart, cost-effective way to extend your transmission’s life, but they won’t reverse severe mechanical wear.
FAQ
Is a transmission additive a permanent fix for slipping?
No, and it’s important to be clear about this. In my experience, a transmission additive is best thought of as a temporary solution or a preventative maintenance step. It can often restore performance for months or even years by reconditioning seals and improving fluid properties, but it does not fix underlying mechanical wear on clutch packs, bands, or solenoids. If your transmission is already severely worn out, an additive will not bring it back from the brink. It addresses symptoms, not the root cause of advanced failure.
Can I use any additive in my CVT transmission?
You must be extremely careful here. I would not recommend using just any additive in a Continuously Variable Transmission (CVT). CVTs operate very differently from traditional automatics, using a special chain or belt and pulleys. They require specific transmission fluid, and using an incompatible additive can cause the belt to slip excessively or damage the pulleys, leading to a very expensive repair. Always use an additive that is explicitly labeled as safe for CVT use.
How long does it take for a transmission additive to work?
You might feel a difference almost immediately, or it might take a few hundred miles of driving. The additive needs to circulate throughout the entire transmission system and begin working on the internal seals. For a minor slip or a rough shift, you could notice an improvement within the first 50-100 miles. For a more persistent issue, it can take a full tank of gas and some varied driving (city and highway) for the treatment to fully integrate and show its full effect. Patience is key.
Will using an additive void my car’s warranty?
It might. This is a critical question to ask before pouring anything into your transmission. Many new car warranties are very specific about using only approved fluids and may explicitly prohibit aftermarket additives. Adding a non-approved chemical could give the dealership grounds to deny a warranty claim on your transmission. If your car is still under warranty, your safest first step is always to take it to the dealer for diagnosis rather than trying a DIY fix with one of the best additives for slipping transmissions.
What’s the difference between a transmission additive and a flush?
They are completely different procedures. An additive is a chemical you mix with your existing transmission fluid to change its properties or condition internal parts. A flush is a service where a machine is used to forcibly remove all of the old fluid and replace it with new fluid. A flush is a more thorough maintenance item, while an additive is a treatment. Sometimes, the best approach is to do a fluid drain and fill (a less aggressive version of a flush) and then add the treatment to the fresh fluid for the best results.