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Chevrolet/GMC 2.8L Duramax Diesel Engine Supplement (GMNA-Localizing-
U.S./Canada-13336155) - 2020 - CRC - 5/6/19
Driving and Operating
57
CLEAN EXHAUST FILTER SEE
OWNER MANUAL NOW DIC
warning messages. If the DIC
message is displayed during PTO
operation, see
for information on how to
clean or regenerate the DPF.
PTO Operational Speed
Control
Variable PTO operational speed
control provides the following
functions:
Cruise Control SET
−
(In-Cab) or
Remote PTO Set 1 Switch
SET :
Press and hold the
accelerator to obtain the desired
engine speed, then press and
release SET
−
on the cruise control.
The current engine speed will be
maintained. This action can be
repeated as desired to capture a
higher rpm value. The PTO set
speed cannot exceed 2900 rpm.
TAP DOWN :
Press and release
SET
−
on the cruise control to
reduce the engine speed by
increments of 100 rpm. The tap
down engine speed increments can
be adjusted by the GM Service Tool.
The Service Tool can enable the
option for adjustment of tap down
engine speed increments through
the Radio Customization menu.
COAST :
Press and hold SET
−
on
the cruise control to reduce the rpm
at 150 rpm/sec until the desired
engine speed is reached or until the
initial PTO Standby Speed is
reached.
In-Cab Cruise CRES or
Remote PTO Set 2 Switch
RESUME :
After a PTO set speed
has been met, a Resume Speed
message is retained after an
application of the brake pedal.
Engine speed will reduce to basic
idle speed. The PTO indicator light
will blink slowly indicating the
previous PTO set speed has been
retained in memory. Press and
rRES on the cruise control
to resume the previous PTO set
speed.
TAP UP :
Press and rRES
on the cruise control to increase the
engine speed by increments of 100
rpm (factory preset value). The tap
up engine speed increments can be
adjusted by the GM Service Tool.
The Service Tool can enable the
option for adjustment of tap up
engine speed increments through
the Radio Customization menu.
ACCEL :
Press and hold +RES on
the cruise control to increase the
rpm by 150 rpm/sec until the
desired engine speed is reached or
until the maximum allowable PTO
set speed is reached. Alternatively,
the engine speed acceleration can
be adjusted through the Radio
Customization menu.