7
maintaining Def Quality
The quality of DEF in the tank must be maintained for the vehicle to run
correctly. Care should be taken to prevent any contaminants from getting into
the fluid. Only GM-approved DEF, or DEF fluid containing the API certified or
ISO 22241 label, should be used.
To meet federal and state requirements, the electronic
onboard warning system is designed to automatically
monitor DEF quality. If poor-quality fluid is detected,
the system will alert the driver. If poor-quality fluid
is not replaced within 200 miles, the vehicle speed
will be limited to 55 mph at the next vehicle start.
If the system’s warnings continue to be ignored,
vehicle speed will ultimately be limited to 4 mph
in accordance with federal and state requirements.
warranty concerns
System damage caused by using incorrect fluid is not eligible for warranty
reimbursement. Care should be taken to avoid introducing any contaminants
into the DEF tank or fluid.
tampering with the exhaust system
No modifications should be made to the exhaust system in the area
between the engine and the Diesel Particulate Filter (DPF). Modifications
to the exhaust routing after the DPF are allowed within guidelines published
on gmupfitter.com
