Chevrolet/GMC 3.0L Duramax Diesel Engine Supplement (GMNA-Localizing-
U.S./Canada-13336148) - 2020 - CRC - 9/5/19
24
Driving and Operating
persists, see your dealer or
additional DIC messages may
display.
Service Emission System
If a problem occurs with the vehicle
emission system, a DIC message
displays along with distance until
vehicle speed is limited. The speed
limitation will occur in a series of
steps with the final speed limitation
of 88 km/h (55 mph) and chimes. In
some cases, this message will clear
itself, indicating that the emission
system was able to correct the
condition. If the DIC message
persists, see your dealer or
additional DIC messages may
display.
Brakes
Exhaust Brake
Exhaust braking is automatically
activated when Tow/Haul Mode is
selected. It maintains the vehicle
’
s
speed by automatically
implementing a shift pattern that
uses the engine and the
transmission to slow the vehicle.
The system will command
downshifts and use the turbocharger
on the engine to reduce the
vehicle
’
s speed when the brake is
applied. The normal tow/haul shift
pattern will return once the vehicle
is on a low grade or when the
accelerator pedal is pressed.
While in the Electronic Range
Select (ERS) Mode, grade braking
is deactivated, allowing the driver to
select a range and limiting the
highest gear available. See
“
Manual
Mode
”
in the owner
’
s manual.
Fuel
Top Tier Fuel
GM recommends the use of TOP
TIER Diesel Fuel to keep the engine
clean, reduce engine deposits, and
maintain optimal vehicle
performance. Look for the TOP
TIER Logo or see
www.toptiergas.com for a list of TOP
TIER Diesel Fuel marketers and
applicable countries.