10 Best Transmission Additive of December 2025

• Lucas Transmission Fix Stops Slip, Hesitation, Rough Shifting In Worn Transmissions And Completely Eliminates Most Seal Leaks
• Fit Type: Universal
• Can be added to existing fluid without draining any out
• Improves shifting

LUCAS

• The original transmission shudder fix
• A concentrated friction modifier formulated specifically for instantly eliminating torque converter lock-up shudder
• Provides four times less wear than regular ATF
• For use in any automatic transmission fluid (not for use in Ford Type F or CVT applications)
• Voted top product by transmission professionals

Lubegard

• The Original Universal ATF Protectant that Eliminates ATF Confusion and the need to stock multiple ATF's - Dramatically reduces friction and wear on metal parts and internal components
• Will not alter the crucial sulfur balance in your transmission fluid, Prevents overheating, Will not harm yellow metals, Inhibits fluid oxidation and foaming
• Contains patented Synergol TMS Technology, a synthetic molecule that tightens the shift cycle without losing the friction modification at lockup, which eliminates shudder
• Extends fluid change intervals, Protects and restores seals for optimum performance, Conditions and restores seals and o-rings
• Does not contain any harmful components such as zinc (ZDDP)/ash, etc., like other competing products, Frees stuck valves and keeps them free, Ensures proper shifts

Lubegard

• Prevents oil loss
• Regenerates seals, cleans and protects
• Improve steering characteristic and reduced the noise
• Damps down shifting operations and protects from wear
• Lowers repair costs and lengthens the service life

Liqui Moly

• 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

• Includes a Formula with Anti-Friction Metal Treatment Technology
• Features Engineering Designed to Treat Metal Surfaces Through a Molecular and Chemical Process
• Offers Molecules that Interact with Metal Surfaces and Chemically Bond to Create a Protective Layer that Reduces Damaging Friction and Heat
• Offers to Treat the Metal Surfaces of Both Standard (Manual) and Automatic Transmissions
• Features a Formula that Promotes Smoother Manual Shifts and Helps Restore Responsiveness in Automatic Transmissions

Prolong Super Lubricants

• Prevents overheating, reducing elevated operating temperatures up to 40 degrees Farenheit - Optimizes total transmission performance
• Eliminates transmission fluid foaming and oxidation and reduces wear throughout the transmission
• Eliminates clutch chatter and torque converter shudder; Softens and modifies harsh shifts making them quicker in duration
• Extends fluid life / Raises the thermal and oxidative stability of the fluid
• Only protectant that increases the fluid’s ability to transfer heat / Protects new seals and permanently restores older seals to a like-new condition, without adverse side effects

Lubegard

• Improves shifting
• Extends fluid life
• AFFORDABLE SOLUTIONS
• Reduces noise and shudder

Lucas Oil

• 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

• Repair Transmission
• Restores Surfaces and Protects Friction Metal Parts From Wear
• Eliminates Surface Defects
• Increases Performance Reliability and Prolongs Service Life Span of Control Mechanisms
• Reduces Noise and Vibrations

XADO