Fuel & DEF Verified Factory Specs

Heavy Duty Diesel Exhaust Fluid (DEF) Dosing Rate Calculator

Calculate SCR Diesel Exhaust Fluid (DEF) consumption rate in Gallons Per Hour, miles per DEF gallon, and DEF tank refill range for EPA2010, GHG14, and GHG17/21 diesel engines.

Engine Rated Horsepower (HP)

Average Engine Load Factor

Average Cruise Speed

MPH

SCR DEF Dosing Rate

Fuel Burn Rate (GPH)

10.57 gal/hr

40.01 Liters/hour

Calculated Fuel Mileage

6.1 MPG

At 65 MPH sustained cruise

DEF Injection Rate

0.317 gal/hr

3% of diesel consumption

DEF Range Per Gallon

205 miles/gal

~3075 miles on 15-gal tank

Commercial DEF Dosing Ratios Across Emission Standards

Selective Catalytic Reduction (SCR) systems inject DEF (32.5% urea) to break down nitrogen oxides (NOx) into harmless nitrogen and water vapor:

EPA 2010 Engines (2.0% Dosing): High EGR rates; burns ~2 gallons of DEF for every 100 gallons of diesel fuel. (Yields ~300+ miles per DEF gallon).
GHG 2014 Engines (2.8% Dosing): Balanced EGR/SCR optimization; burns ~2.8 gal DEF per 100 gal diesel. (Yields ~250 miles per DEF gallon).
GHG 2017 / 2021 Engines (3.5% Dosing): Low EGR calibration to maximize fuel economy; relies more heavily on SCR, burning ~3.5 gal DEF per 100 gal diesel. (Yields ~200-220 miles per DEF gallon).

Related Heavy Diesel Engineering Tools

Cross-reference other factory specifications and diagnostic tools for commercial diesel engines:

Pillar 3 →

Valve Lash & Overhead

Intake, exhaust, & Jake brake clearances.

Pillar 1 →

Oil & Coolant Sump

Standard vs deep pan fill volumes.

Pillar 4 →

Head Bolt Torque

Torque-to-yield angle stages & sequences.

Pillar 2 →

SPN Fault Code Lookup

J1939 fault diagnostics & sensor pins.

Technical Reference Citation: ISO 22241 Diesel Exhaust Fluid Specifications & EPA SCR Compliance

View Engineering Methodology & Standards →