Fleet trial program

Stop losing $5,000 SCRs to bad DEF.

NüDef stabilizes diesel exhaust fluid and prevents the crystallization that destroys SCR injectors. Try it on your fleet — no commitment.

  • Dedicated fleet rep, not a phone tree
  • Custom dose schedule for your DEF volume + engine mix
  • 30-day check-in to verify SCR fault-code reduction
  • Volume pricing if you decide to roll out fleet-wide
How it works ↓

Apply for fleet trial

Talk to a NüDef fleet rep within 1 business day.







    Engine mix * (check all that apply)

    Primary application *


    $5,000
    AVG SCR REPAIR COST
    1–3 days
    DOWNTIME PER REPAIR
    25 gal
    PER 8.45 FL OZ BOTTLE
    ISO 22241
    WARRANTY-SAFE SPEC

    The problem

    DEF crystallizes inside hot SCR systems.

    Once urea concentration drifts out of spec — from heat cycling, evaporation in storage, or low-quality DEF — solid crystals form on injectors and dosing modules.

    Crystallization is the #1 cause of premature SCR failure on Tier 4 diesel engines. Replacing a fouled injector or DPF assembly runs $3,500–$8,000 and pulls the truck out of service for days.

    Fleets running long-haul, oil-field, or vocational duty cycles see this fastest.

    The fix

    NüDef keeps DEF in spec.

    • Stabilizes urea concentration across temperature swings
    • Prevents crystal formation on injectors and dosing valves
    • Extends DEF shelf life from 12 months to 24+ months
    • One 8.45 fl oz bottle treats 25 gallons of DEF

    Compatible with all SCR-equipped diesel engines including Cummins, Detroit Diesel, Volvo, PACCAR, Mack, Caterpillar, and International. ISO 22241 compliant.

    Fleet Trial FAQ

    Ready to stop losing SCRs?

    Apply for a fleet trial — no commitment, no auto-billing.

    Apply for fleet trial →