Our #1 BlueDEF pick
Top-ranked Diesel Exhaust Fluid (DEF) in our BlueDEF lineup, scored independently on effectiveness, health, and environmental impact. No paid placements.
As an Amazon Associate I earn from qualifying purchases. Full disclosure
BlueDEF is Old World Industries' consumer-facing diesel exhaust fluid brand and holds the #1 DEF brand position in the U.S. retail market. The product line is manufactured to ISO 22241 standards and carries API DEF Certification, which requires third-party spot testing of retail samples to verify the 32.5% urea concentration specification.
Old World Industries is headquartered in Northbrook, Illinois, and also markets the PEAK antifreeze and coolant line. BlueDEF is available through Walmart, AutoZone, O'Reilly Auto Parts, Amazon, and truck stop networks nationally.
Affiliate disclosure: CarCareTruth is reader-supported. As an Amazon Associate I earn from qualifying purchases. We may also earn commissions from other retailers linked on this page, at no extra cost to you. Affiliate revenue never influences our scores or rankings. Full disclosure
As an Amazon Associate I earn from qualifying purchases. Full disclosure