Typical Diesel Exhaust Fluid (DEF) Usage Chart Primary Trailer Tow / Aggressive or City Drive Style Primary Trailer Tow / Aggressive or City Drive Style Primary Trailer Tow / Aggressive or City Drive Style Primary Trailer Tow / Aggressive or City Drive Style Pick-up w/ 3.31 axle Pick-up w/ 55 axle Pick-up w/ 73 axle Pick-up w/ 4.30 axle Primary Trailer Tow / Aggressive or City Drive Style Steady Highway drive Steady Highway drive Steady Highway drive Steady Highway drive Chassis Cab – Non-PTO Steady Highway drive Chassis Cab –-PTO Continuous PTO usage 1,000 2,000 Minimal PTO usage 3,000 4,000 5,000 6,000 7,000 DEF Distance to EMPTY (Miles) 8,000 9,000 10,000