10 Best Transmission Cleaner Additive of December 2025

• STP Super Concentrated High Mileage Engine Flush cleans and prepares your vehicle's engine for new oil
• STP High Mileage Oil Treatment + Stop Leak's high-viscosity formula, complete with anti wear agent ZDDP, is specially formulated to help fight metal-to-metal friction by providing a thicker cushion between moving engine parts
• STP High Mileage Transmission Stop Slip + Leak Repair is scientifically engineered with Anti-Wear additives and with antioxidants to help stabilize transmission fluid; formulated to help recondition and protect transmission seals, eliminate slip and reduce rough shifting
• STP Ultra 5-in-1 Fuel System Cleaner contains high-performance detergents and friction modifiers that come together to form a one-source solution to help to save gas by deep cleaning the entire fuel system, restore peak performance, reduce friction, prevent ethanol deposits and inhibit corrosion

STP

• Fit type: Vehicle Specific
• Made in United States
• Package Dimensions : 7.45 L x 3.38 H x 4.22 W (inches)
• Package Weight : 1.63 pounds

Motorcraft

• Reduces operating temperatures
• Eliminates station from all automatic & CVT transmissions
• Reduces coefficient of friction
• Transmission station eliminator minimizes metal to metal contact
• Eliminates rust & corrosion

Hot Shot's Secret

• EXTEND THE LIFE OF YOUR VEHICLE: zMAX Micro-lubricant is simple and easy to use. Formula soaks into metal surfaces, which improves lubricity and reduces carbon deposit build-up while boosting performance and protecting vital parts in your car or truck.
• FUEL SYSTEM CONDITIONER: Use at your routine oil change or every 6k miles to lubricate the fuel injector system. The multipurpose formula conditions the pumps and the nozzles, while reducing carbon residue from valves and pistons to restore performance.
• FUEL SYSTEM EFFICIENCY: Make zMAX part of your car or truck’s routine maintenance! Reduces engine wear, enhances performance and improves fuel efficiency for gas or diesel vehicles. This cost saving product lowers emissions, is eco-friendly and USA-Made.
• TRUSTED BY PROFESSIONALS & DEALERSHIPS: Stock zMAX in your garage to regularly treat your car like a professional. From local repair shop mechanics to major car dealership groups, our formula is road tested and mechanic trusted.
• REPUTABLE QUALITY AND PERFORMANCE: zMAX is proud to be the Official Micro-lubricant of Speedway Motorsports. Proven and trusted for over 80 years, zMAX helps save money at the pump and extends your engine’s life.

zMAX

• PROTECT YOUR VEHICLE: zMAX Transmission Formula is easy to use! Micro-lubrication soaks into metal surfaces improving lubrication to reduce gear wear and varnish buildup. Keeps seals supple, preventing leaks and improving shifting.
• TRANSMISSION EFFICIENCY: Improve performance by adding the formula to your transmission fluid to reduce slippage and rough shifting. Brings back smooth shifting gears resulting in an improved response. Add every time you change your transmission fluid.
• TRANSMISSION LUBRICANT: Cleans varnish for smoother shifting and lubricates bearings, gears, and the hydraulic system. Perfect for both automatic or manual transmissions. Not for use in CVT transmissions. Does not void manufacturer's warranties.
• ECONOMICAL PREVENTATIVE MAINTENANCE: Pour into transmission fluid to keep the gears lubricated and in top condition. The eco-friendly formula is industry tested, mechanic trusted and improves the performance and the driving experience.
• TRUSTED QUALITY AND PERFORMANCE: zMAX is proud to be the Official Micro-lubricant of Speedway Motorsports. Trusted for over 80 years, the USA made Transmission Formula saves money at the pump and extends the engine life of all your vehicles.

zMAX

• Helps fluid systems work smoother and last longer
• Dissolves and liquefies harmful gum and varnish buildup in fluid
• Cleans and lubricates valve bodies, shift actuators and solenoids, controls moisture
• Safe in most types of automatic transmission fluid, hydraulics, or power steering fluid systems
• Safe for conventional and synthetic fluids

Sea Foam

• Helps eliminate transmission shudder
• Restores ATF additive content and provides additional protection to transmissions
• Prevents transmission leaks and aids high mileage transmissions by lubricating seals
• Can be added anytime or while doing a transmission fluid change, leave adequate fill space
• Helps erratic shift and loss of torque

Slick 50

• Please see Product Description regarding the California Proposition 65 Warning
• RAVENOL advanced fluid technology from Germany Improves transmission performance, efficiency, reduces wear and extends transmission life
• Fluid formulation has Factory Approval or Meets your vehicle manufactures specific specification and is engineered for extended long life fluid change intervals
• Kit Includes correct amount of RAVENOL transmission fluid, Filter and Hardware for standard drain pad fluid change (see the product image)
• Before Ordering, READ IMPORTANT APPLICATION or FITMENT NOTES in the Product Details section below. Confirm this product fits your vehicle years, make, model, and transmission!

Blau

• RESTORES AND PROTECTS automatic transmissions from wear.
• Protects from OVERHEATING.
• EASES gear changes.
• PROTECTS FROM WEAR while changing gears.
• DECREASES OR ELIMINATES unwanted noise and vibration.

Resurs

• Add to fuel to help clean fuel injectors and restore injector spray patterns
• Adds lubricity to upper cylinders
• Helps recover lost MPG and reduce exhaust emissions
• Concentrated formula treats up to 25 gallons
• Safe for all types of gasoline fuel injection engines

Sea Foam