Bar's Leaks Transmission Fix additive 11.5 oz – stops leaks, restores seals & improves shift feel

Bar's Leaks 1415 Transmission Fix is a synthetic-blend additive designed to stop and prevent transmission leaks while restoring seal flexibility and improving shift feel.

If your vehicle’s transmission is showing signs of leaking, slipping, hard shifts, or excess noise, this concentrated 11.5 oz treatment works with automatic, manual, CVT and DCT systems to refresh seals, reduce wear, and help clean internal surfaces. Formulated for both domestic and import vehicles, the product blends seal conditioners, anti-wear agents and detergents to address common performance and sealing problems without the need for parts replacement in many cases.

How does this product stop existing leaks and prevent new ones?

The formula contains seal-softening and conditioning ingredients that penetrate rubber and elastomer components to restore pliability and close shrinkage gaps. By rejuvenating drying seals, it reduces seepage paths and helps maintain the improved condition over time when used as directed.

• Contains seal conditioners to swell and soften hardened gaskets and O-rings.
• Compatible with typical transmission fluids so it mixes easily into system oil.
• Can be used proactively to reduce future drying and cracking of seals.

Will it improve shifting, slipping or transmission noise?

Yes — the treatment includes anti-wear and extreme-pressure additives that help enhance metal-to-metal friction properties and reduce slippage. Users often notice smoother engagement, fewer jerks, and reduced shudder as bands and clutch surfaces regain more consistent friction characteristics.

• Helps control slipping, hard shifts, and shutter by restoring friction balance.
• Contains agents to reduce wear on bands and clutch plates for better shift feel.
• May lower certain noise sources related to fluid degradation and surface wear.

Can it clean internal deposits or improve fluid condition?

The product includes detergents, dispersants and antioxidants intended to help loosen sludge and varnish on metal parts and in fluid passages. These cleaning components assist the transmission’s fluid filtration and circulation, promoting a cleaner operating environment for friction surfaces and valves.

• Detergents and dispersants aid in removing sludge and varnish buildup.
• Antioxidant ingredients help control fluid degradation at higher temperatures.
• Supports cleaner valve bodies and passages when used as recommended.

How much should I use and which vehicles is it suitable for?

One 11.5 oz bottle treats systems with 7 to 11 quarts of total transmission fluid. For smaller systems (3 to 6.9 quarts), use half a bottle; for larger systems, add one bottle per each additional 9 quarts. The formulation is intended for use in automatic, manual, CVT and DCT transmissions across domestic and imported vehicles, but always follow OEM recommendations.

• Dosing: full bottle for 7–11 quarts; half bottle for 3–6.9 quarts; extra bottle per 9 quarts beyond capacity.
• Works with most AT, MT, CVT and DCT systems—check manufacturer guidelines first.
• Simple pour-in treatment—no special tools required; follow safety and service instructions.

Who is this for? This Bar's Leaks Transmission Fix is aimed at car owners and technicians who want a practical, in-field remedy for common transmission seal and performance issues without immediate disassembly. It’s a good fit for vehicles showing light-to-moderate leaks, slipping, hard shifting, or fluid-related noise where a conditioning and cleaning treatment may restore proper function. For severe mechanical failures, extensive metal damage, or complete seal loss, a professional inspection and repair may still be necessary.