Archoil Diesel Fuel System Kit AR6400-D (12 oz) + AR6500 (40 oz) — Injector Cleaner & Lubricity Boost

The Archoil Diesel Fuel System Kit (AR6400-D 12 oz + AR6500 40 oz) is a two-step fuel restoration and maintenance system designed to remove injector deposits, improve lubricity, and boost cetane for smoother diesel engine operation.

This kit pairs a concentrated one-time deep cleaner with a follow-up treatment to restore and then protect modern diesel fuel systems. AR6400-D is formulated for an intensive clean that tackles stuck deposits and varnish in injectors and combustion chambers, while AR6500 provides ongoing protection, lubricity improvement, and cetane enhancement to reduce wear and support consistent performance across diesel engines and equipment.

How does the two-step cleaning and maintenance process work?

Start with AR6400-D as a focused reset: it cleans stubborn deposits and restores proper injector spray patterns. After the deep clean, add AR6500 regularly to maintain cleanliness, reduce new deposit formation, and keep system components lubricated.

• AR6400-D: 12 oz treats 30–40 gallons for an intensive clean.
• AR6500: 40 oz treats up to 400 gallons as a maintenance dose.
• Sequence: one-time AR6400-D treatment, then AR6500 at every fill or scheduled intervals.
• Works in modern high-pressure common-rail (HPCR) systems and older diesels.

What benefits will I notice after using this kit?

Users commonly report restored throttle response, reduced rough idling, and smoother acceleration due to cleaner injectors and improved combustion. Over time, the maintenance treatment helps reduce deposit-related issues that can affect turbochargers, DPF performance, and fuel economy.

• Improved injector spray and combustion efficiency.
• Reduced need for frequent DPF regens and lessened turbo deposit build-up.
• Enhanced drivability through faster ignition and smoother power delivery.
• Ongoing protection against wear-sensitive components like CP4 pumps.

How does AR6500 protect the fuel system and components?

AR6500 is engineered to improve lubricity and raise cetane, supporting component longevity and more reliable ignition. Laboratory testing shows significant lubricity improvement, and the cetane boost helps fuels ignite more readily for steadier combustion patterns.

• ASTM D6079-tested lubricity improvement to help protect high-pressure pumps.
• Cetane increase of up to +8 for crisper ignition timing and smoother running.
• Deposit control to limit buildup that impairs turbos and DPFs.
• Suitable for routine dosing at fill-ups for continuous protection.

Will this kit work in my diesel vehicle or equipment?

Yes — the formulations are compatible with a wide range of diesel engines, from light trucks and SUVs to agricultural and construction equipment. The products are safe for modern HPCR fuel systems when used as directed, and they address both cleaning and maintenance concerns across engine types.

• Compatible with all diesel engine types, including late-model common-rail systems.
• Use AR6400-D periodically when deposits are suspected, then follow AR6500 regularly.
• Not a fuel additive to replace mechanical service; complements routine maintenance.
• Helps protect wear-prone components in high-pressure fuel systems.

Who is this for: The Archoil Diesel Fuel System Kit is aimed at diesel owners and fleet managers who want a practical, chemistry-based approach to restoring injector performance and protecting fuel-system components. It's well suited to people noticing rough running, sluggish response, frequent DPF regenerations, or who operate heavy-use equipment and want to extend component life while improving drivability and fuel stability. This kit is also a good preventive option for vehicles with high-pressure pumps that require improved fuel lubricity and for anyone who prefers a two-step deep-clean plus maintenance routine rather than repeated single-product applications.