GMC Duramax Diesel 2015 Owner's Manual page 9

1-4 In Brief
Additionally, some diesel truck
fueling stations or retailers may
have DEF for purchase. For
®
vehicles with an active OnStar
subscription, OnStar can help to
locate a DEF retailer. See
Customer Assistance Offices in
the owner manual for phone
numbers to assist you in contacting
a GM dealer. See Recommended
Fluids and Lubricants on page 11-8.
As the DEF tank becomes low on
fluid, warnings begin with
approximately 1 600 km (1,000 mi)
of remaining range. These warnings
will increase in intensity as the tank
becomes empty. Once the tank is
empty, the vehicle speed will be
limited. If there is an issue with the
quality of the fluid or the exhaust
fluid system, warnings will be
displayed in the Driver Information
Center (DIC). See Diesel Exhaust
Fluid on page 9-13.