Emission Reduction Fluid Tank Draining

WARNING: This page is about a different variant/trim than selected.

Before performing the first steps, review the Emission Reduction Fluid and Emission Reduction Fluid Handling .
CAUTION:
The diesel exhaust fluid (DEF) system is part of the emission system for this vehicle and must be serviced while observing extreme care to prevent foreign contamination of any kind from entering this system. If extreme care is NOT taken to prevent contamination from dirt, debris, fluids other than DEF, etc., reduced performance and/or damage to the DEF system may result.
- Cleanliness of the diesel exhaust fluid (DEF) system is crucial to ensure proper operation. Before opening any part of the DEF system, ensure connections and joints are thoroughly clean and dry of any dirt, debris or other contaminants. Use only low pressure water and low pressure air, as directed.
- Diesel exhaust fluid (DEF) will have a tendency over time to develop areas of dried crystallization residue. Crystallization residue is a normal process for this fluid. Dried DEF crystallization residue can be wiped away or flushed away with clean water, depending on location of the crystallization.
Remove the emission reduction tank filler cap (1).

Fig 1: Emission Reduction Fluid Tank Filler Cap
Courtesy of GENERAL MOTORS COMPANY
Insert the hose from the pump devise into the emission reduction fluid tank.
CAUTION: The diesel exhaust fluid (DEF) must be drained by a clean dedicated siphoning pump and hose. It must NOT have any traces of gasoline, diesel fuel or any oil based substances. If extreme care is NOT taken to prevent contamination from fluids other than DEF, reduced performance and/or damage to the DEF system may result.
Using a hand or air operated pump device, drain as much emission reduction fluid from the tank as possible into an approved container and dispose of properly.
Using a clean white shop towel, carefully dry around the fluid tank fill port by hand to ensure dryness and cleanliness.
Fill the tank with clean emission reduction fluid. Refer to Adhesives, Fluids, Lubricants and Sealers .
NOTE: The capacity of the emission fluid tank is 18.5 liters (4.9 gal).