GMC Terrain: Diesel Exhaust Fluid / Filling the DEF Tank

Caution

Use only DEF that is GM approved, or fluid containing the API certified or ISO 22241 label. The use of other fluids could damage the system, requiring costly repairs that will not be covered by the vehicle warranty.

Caution

Do not mix fuel with DEF, and do not put DEF in the fuel tank. This could lead to costly repairs that might not be covered by the vehicle warranty.

It is recommended to fill the DEF tank on level ground and when the vehicle is not running. When adding fluid, it is recommended to fill the DEF tank.

Caution

Do not overfill the DEF tank and do not allow DEF to contact the finished surfaces of the vehicle, as it could damage the vehicle finish. If DEF is spilled during filling, wipe any affected surface with a damp cloth.

Do not top off the DEF tank. If using a bottle or jug to refill DEF, follow the instructions on the container label and use a dedicated fill aid. In certain cold conditions, it is possible to find some frozen DEF in the DEF fill pipe opening. If this condition prevents the filling of a DEF tank, place the vehicle in a warm garage overnight.

For information on how to fill the DEF tank, see Filling the Tank (Gasoline) or Filling the Tank (Diesel).