Stanadyne Diesel Fuel Additive 12-Pack (½‑Pint/8oz) — Injector Cleaner & Lubricity, ULSD/B20 Safe

This kit contains twelve 8-ounce bottles of Stanadyne Performance Formula (part #38564), offering a practical, regular-use supply for light- and heavy-duty diesel vehicles. Formulated to address deposit buildup, varnish and friction in fuel systems, the additive is compatible with ULSD and B20 biodiesel blends and is safe for exhaust aftertreatment systems. Use it routinely to maintain throttle response and optimize combustion without altering service intervals.

How does Stanadyne Performance Formula help my diesel engine perform better?

The formula works by cleaning injectors and lubricating moving parts in the fuel system to recover lost horsepower and smoother throttle response. By reducing deposits and friction, combustion becomes more consistent and efficient.

• Contains detergents and lubricity agents that clear injector deposits.
• Helps restore lost horsepower and torque through cleaner spray patterns.
• Improves throttle response and reduces rough idling caused by fouled components.

Will this additive improve fuel economy and when should I use it?

Regular treatments can help recover and maintain fuel economy by promoting more complete combustion and reducing friction in the fuel system. For best results, add the recommended dose at each fill-up and use an injector cleaner treatment four to six times per year.

• Designed for routine use: treat with each tank fill for ongoing maintenance.
• Use the Performance Formula Injector Cleaner 4–6 times annually for deeper cleaning.
• Works with both standard highway diesel and B20 biodiesel blends.

Is this product suitable for cold weather or winterized fuels?

Performance Formula includes components that offer cold-weather protection and anti-gel performance, though Stanadyne also sells dedicated cold-weather and lubricity blends for extreme conditions or very dry fuels. This pack gives you flexibility for most climate scenarios while protecting system components from corrosion.

• Provides anti-gel protection to reduce waxing and fuel gelling risk in moderate cold.
• Includes corrosion inhibitors to protect fuel-system metals and seals.
• Compatible with ULSD and works alongside Stanadyne cold-weather products if needed.

How does this product protect emissions systems and modern diesel hardware?

Stanadyne Performance Formula is formulated to be exhaust aftertreatment safe, meaning it won’t harm diesel particulate filters or selective catalytic reduction systems when used as directed. It balances cleaning with components that preserve emissions-control function while keeping injectors and pumps lubricated.

• Aftertreatment-safe formulation avoids negative impacts on DPF and SCR systems.
• Lubricity additives reduce wear on pumps and injectors in ultra-low sulfur diesel (ULSD).
• Non-corrosive ingredients help protect fuel lines, seals, and metal components.

Who is this for: The 12-pack of ½-pint Stanadyne Performance Formula is intended for fleet managers, commercial operators, diesel owners with multiple vehicles, and do-it-yourself enthusiasts who prefer keeping regular treatment supplies on hand. It’s ideal if you want a single, versatile additive that addresses injector cleanliness, lubricity, mild cold-weather protection, and fuel-economy recovery while remaining compatible with modern diesel fuels and emissions hardware. If you operate in extreme cold or use very dry fuels, consider combining this product with Stanadyne’s specialized cold-weather or lubricity-only blends for targeted protection.