Stanadyne Diesel Fuel Additive 4 x 8 oz Performance Formula — Injector Cleaner, Cetane Boost & Lubricity

Stanadyne Performance Formula 38564 is a concentrated diesel fuel additive designed to clean fuel systems, boost combustion quality, and help restore lost horsepower and fuel economy.

This four‑bottle pack contains four 8‑ounce doses of Stanadyne Performance Formula, a multi‑function diesel treatment formulated for modern ultra‑low sulfur diesel (ULSD) and up to B20 biodiesel blends. It combines detergents, cetane enhancement, lubricity agents, corrosion inhibitors and demulsifiers to address common fuel problems — from injector deposits to moisture and cold‑weather performance — without affecting exhaust aftertreatment systems.

How does this additive improve engine performance?

Performance Formula works on fuel delivery and combustion. Detergents remove deposits that impair spray patterns and injection timing while the cetane improver promotes faster ignition and a steadier burn, which can yield smoother operation and restored power.

• Removes injector and pump deposits for consistent spray patterns
• Raises effective cetane for improved ignition quality
• Helps recover lost horsepower and throttle response

Will it help my fuel economy and emissions?

By improving combustion efficiency and cleaning the fuel system, the additive can reduce unburned fuel and soot formation. Independent measurements have shown average fuel‑use improvements, and the cleaner burn typically lowers visible smoke and particulate output.

• Supports more complete combustion for better miles per gallon
• Reduces smoke and particulate formation from incomplete burning
• Formulated to be compatible with exhaust aftertreatment devices

How does it protect fuel system components and handle water?

The formula includes lubricity agents to counteract the low lubrication of ULSD and corrosion inhibitors to shield metal parts. Special demulsifiers help separate tiny water droplets so filters and separators can remove them more effectively, reducing corrosion and wear.

• Restores lubricity to protect pumps, injectors and seals
• Inhibits rust and corrosion in the fuel system
• Improves water separation for easier removal at the filter

Is it suitable for cold weather and biodiesel blends?

Yes — the additive contains cold‑flow performance agents that can lower pour and cold‑filter‑plug points depending on the base fuel, helping prevent gelling in cooler conditions. It’s also safe for diesel blends containing up to 20% biodiesel (B20), maintaining increased water separation in those blends.

• Helps lower pour point and reduce cold filter plugging
• Compatible and tested with biodiesel up to B20
• Does not contain alcohol and is formulated for ULSD fuels

Who this product is for: Vehicle and equipment owners who want a ready‑to‑use diesel treatment to clean injectors, restore lost performance, protect fuel system components, and improve cold‑weather reliability. It’s suitable for passenger diesels, light‑ and medium‑duty trucks, agricultural and construction equipment, and fleets that use ULSD or up to B20 biodiesel and want a maintenance‑grade additive to address fuel quality issues.