Rislone DEF Crystal Clean Diesel DEF & SCR Emission Cleaner — 6-Pack, dissolves urea crystals & restores SCR flow

Rislone DEF Crystal Clean is a concentrated cleaner formulated to dissolve white crystallization and restore proper operation of Diesel Exhaust Fluid (DEF) / AdBlue SCR emission systems.

Built for modern diesel vehicles that use Selective Catalytic Reduction (SCR) and DEF/AdBlue systems, this six-pack provides targeted cleaning agents and surfactants that are safe for all approved urea-based fluids. The formula is designed to break down the white crystal deposits that accumulate in tanks, pumps, heaters, lines and reactors, helping the SCR system run more reliably and reducing the risk of limp-mode events caused by blocked components. Use it as part of routine maintenance or when you suspect crystallization is affecting performance.

How does Rislone DEF Crystal Clean work inside an SCR system?

The product combines DEF-compatible cleaning chemistry and detergents to dissolve and loosen urea-based crystals that form on internal SCR components. By re-dispersing deposits, it restores normal fluid flow and sensor function without harming approved DEF fluids or emission hardware.

• Targets deposits in tank, pump, heater, sender, lines and injector.
• Safe for DOC, DPF, SCR and ammonia slip catalysts when used as directed.
• Compatible with all approved DEF/AdBlue and AUS32 formulations.

How do I add it to my vehicle and how much should I use?

Pour directly into the DEF/AdBlue tank (look for the blue fill cap); do not add to the diesel fuel tank. Dosage varies by vehicle tank size to ensure the cleaning concentration is correct.

• Cars / small SUVs (3–5 gal DEF): use about half a bottle per service.
• Light trucks & mid-to-large SUVs (5–9 gal DEF): use one full bottle.
• Medium/heavy-duty trucks (10–20 gal DEF): use two bottles per service.
• Top up with DEF after pouring; if issues persist after ~250 miles, repeat or seek mechanical inspection.

What problems can this cleaner help prevent or resolve?

Crystallization in DEF systems can restrict flow, confuse sensors and reduce SCR effectiveness, which may increase fuel use or trigger reduced-power modes. Regular use helps minimize buildup and maintain consistent SCR operation.

• Reduces white crystal buildup that blocks pumps and lines.
• Helps prevent limp-mode or reduced engine power related to DEF faults.
• Recommended maintenance interval: approximately every 5,000 miles for prevention.

Is Rislone DEF Crystal Clean safe for my vehicle’s warranty and DEF fluid?

The formulation is designed not to void new vehicle warranties and is compatible with the full range of approved urea-based DEF products. Always follow manufacturer guidance for filling procedures and vehicle-specific service recommendations.

• Works with AdBlue, AUS32, ARLA 32, BlueTEC, DEF UREA and similar fluids.
• Use only in the DEF tank—do not introduce into the diesel fuel system.
• Some vehicles require a filling adapter or funnel for proper installation.

Who is this for: Rislone 4784-6PK DEF Crystal Clean is aimed at diesel vehicle owners and fleet managers who want a preventive maintenance solution for SCR and DEF systems — especially vehicles driven at low speeds, with frequent stops, or short runs that are more prone to urea crystallization. It's also useful for service shops and technicians looking to address symptoms of DEF-system blockages without replacing hardware. Always follow vehicle manufacturer instructions and consider professional inspection if diagnostic lights remain after treatment.

Ingredients

Cleaning agents and surfactant detergents