I have purchased Peak Blue DEF and DEF from a local diesel shop and neither had "use by" or production dates on them. Guess I'll store it my basement where it stays cool all year long.
2011 Chevy Silverado 3500HD CCLB SRW LTZ 4X4 DA Blue Granite Metallic, Bed Rug bed liner, Luverne SS running boards, PML diff. cover, Air Lift air bags, Handy fifth wheel tail gate.
Towing: 2009 Montana Mountaineer 347THT Toy Hauler.
2005 Chevy Silverado 3500 CCLB SRW LT 4X4 DA Silver Birch Metallic
2004 GMC Sierra 2500HD EXLB SE 4X4 DA Sand Beige Metallic