1999 GMC C-SERIES cruise control

yellowblue
2-32
To tilt the wheel, hold the steering wheel and pull the
lever. Move the steering wheel to a comfortable level,
then release the lever to lock the wheel in place.
Turn Signal/Multifunction Lever
The lever on the left side of the steering column
includes your:

Turn Signal and Lane Change Indicator

Headlamp High/Low Beam Changer

Windshield Wipers

Windshield Washer

Cruise Control (If Equipped)
ProCarManuals.com

yellowblue
2-36 Cruise Control (If Equipped)
With cruise control, you can
maintain a speed of about
30 mph (48 km/h) or more
without keeping your foot
on the accelerator. Cruise
control does not work at
speeds below about 30 mph
(48 km/h).
If you have an automatic transmission and you apply
your brakes, the cruise control will shut off.
If you have a manual transmission and you apply your
brakes or push the clutch pedal, the cruise control will
shut off.CAUTION:

Cruise control can be dangerous where you
can't drive safely at a steady speed. So,
don't use your cruise control on winding
roads or in heavy traffic.

Cruise control can be dangerous on
slippery roads. On such roads, fast changes
in tire traction can cause needless wheel
spinning, and you could lose control. Don't
use cruise control on slippery roads.
ProCarManuals.com

yellowblue
2-37
Setting Cruise Control
CAUTION:
If you leave your cruise control switch on when
you're not using cruise, you might hit a button
and go into cruise when you don't want to. You
could be startled and even lose control. Keep the
cruise control switch off until you want to use it.
1. Move the cruise control switch to ON.
2. Get up to the speed you want.
3. Press in the SET button at the end of the lever and
release it.
4. Take your foot off the accelerator pedal.Resuming a Set Speed
Once you're going about 30 mph (48 km/h) or more,
you can move the cruise control switch from ON to
R/A (Resume/Accelerate) for about half a second.
The vehicle will return to your chosen speed and
stay there.
If you hold the switch at R/A longer than half a second,
the vehicle will keep going faster until you release the
switch or apply the brake, so unless you want to go
faster, don't hold the switch at R/A.
If the switch is held at R/A for longer than 200 seconds,
the cruise control will automatically turn off. The cruise
control function will be made available again the next
time the engine is restarted.
ProCarManuals.com

yellowblue
2-38
Increasing Speed While Using Cruise Control
There are two ways to go to a higher speed:

Use the accelerator pedal to get to the higher speed.
Press the button at the end of the lever, then release
the button and the accelerator pedal. You'll now
cruise at the higher speed.

Move the cruise switch from ON to R/A. Hold it
there until you get up to the speed you want, and
then release the switch. To increase your speed in
very small amounts, move the switch to R/A for less
than half a second. Each time you do this, your
vehicle will go about 1 mph (1.6 km/h) faster.
If the switch is held at R/A for longer than
200 seconds, the cruise control will automatically
turn off. The cruise control function will be made
available again the next time the engine is restarted.Reducing Speed While Using Cruise Control
Press in the button at the end of the lever until you reach
the lower speed you want, then release it.
To slow down in very small amounts, tap the button for
less than half a second. Each time you do this, you'll go
1 mph (1.6 km/h) slower.
If the button is held for longer than 15 seconds, the
cruise control will automatically turn off. To make
cruise control available again, the cruise switch must be
moved to OFF then back to ON.
Passing Another Vehicle While Using Cruise Control
Use the accelerator pedal to increase your speed. When
you take your foot off the pedal, your vehicle will slow
down to the cruise control speed you set earlier.
ProCarManuals.com

yellowblue
2-39
Using Cruise Control on Hills
How well your cruise control will work on hills depends
upon your speed, load and the steepness of the hills.
When going up steep hills, you may want to step on the
accelerator pedal to maintain your speed. When going
downhill, you may have to brake or shift to a lower gear
to keep your speed down. Of course, applying the brake
or clutch takes you out of cruise control. Many drivers
find this to be too much trouble and don't use cruise
control on steep hills.
Ending Cruise Control
There are different ways to turn off the cruise control:

Step lightly on the brake pedal.

Push the clutch pedal, if you have a
manual transmission.

Move the cruise switch to OFF.
Erasing Speed Memory
When you turn off the ignition, your cruise control set
speed memory is erased.Trailer Brake Hand Control Valve
(Option)
If your vehicle has this feature, it is mounted on the
steering column.
This control lets you apply the trailer brakes without
applying the tractor brakes. You can apply the trailer
brakes a little or apply them all the way if you have to.
Use this control only when you're driving. Don't use it
for parking or to hold the rig on a hill.
ProCarManuals.com

yellowblue
4-31
Power Take-Off (PTO) (If Equipped)
Before using a PTO, refer to the body builder's or
operator's instructions.
To engage a PTO:
1. Make sure the vehicle is stopped.
2. Shift the transmission into NEUTRAL (N) or
PARK (P), if equipped.
3. The brake or clutch pedal must be pressed and
released once before PTO can be enabled. Do not
hold the brake or clutch pedal down.4. The cruise control switch must be in ON prior to
engaging the PTO switch to enable PTO operation.
This sets the PTO base engine idle at 1200 rpm.
5. Use SET/COAST to change the engine speed to the
lower preset value of 1400 rpm. Use
RESUME/ACCEL to change the engine speed to the
upper preset value of 1800 rpm. You may toggle
between upper and lower by moving the switch
between SET/COAST and RESUME/ACCEL.
The PTO will become inoperative when any of the
conditions are changed or the CHECK GAGES light
comes on.
ProCarManuals.com

yellowblue
7-20
(16) = Check spring-to-axle U-bolts and shackle bolts
for proper torque. See the service manual for torque
sequence and specifications. When parts are replaced,
the torque must be checked and adjusted more often
during the first 6,000 miles (10 000 km). Check torque
at 500 miles (800 km) and 2,000 miles (3 000 km) after
first use of parts.
(17) = Check complete exhaust system and cab areas
near the exhaust system for broken, damaged, missing or
out
-of-position parts. Also inspect for open seams,
holes, loose connections or other conditions which could
let exhaust fumes seep into the driver compartment.
Needed repairs should be made at once. To help
maintain system integrity, replace exhaust pipes
whenever a new muffler is put on.
(18) = Check all engine drive belts for cracks, fraying,
wear and proper tension. Adjust or replace as needed.
(19) = Check throttle linkage for damaged or missing
parts (including throttle return springs), interference or
binding. Fix any problems at once. Do not lubricate
accelerator and cruise control cables.
(20) = With the engine off and below normal operating
temperature, check to see that the thermostatically
controlled engine cooling fan can be rotated by hand on
viscous
-operated drives. Replace as needed.(21) = Check shields and underhood insulation for
damage or looseness. Adjust or replace as needed.
(22) = Lubricate caliper housing, caliper support spring
and caliper support key.
(23) = Wheel bearing service:

Grease type
-- Clean, inspect and lubricate with the
proper wheel bearing grease at designated intervals
or when hubs are removed. See ªRecommended
Fluids and Lubricantsº in the Index.

Oil
-filled type -- Some wheel bearings are lubricated
by rear axle lubricant. When you have oil
-filled
hubs, use lubricant identical to that used in your rear
axle. Lubricant change intervals are the same for
front and rear axles. However, you must maintain oil
level at the OIL LEVEL mark between change
intervals. See ªRecommended Fluids and
Lubricantsº in the Index.
(24) = Check the air intake system installation to see
that gaskets are seated properly and all hose
connections, fasteners and other components are tight.
For gasoline engines, also check to be sure the air
cleaner housing is properly seated, that the cover fits
tightly and that the wing nut is tight. Tighten
connections and fasteners or replace parts as required.
ProCarManuals.com

yellowblue
9-3
Cooling System
Capacity 6-74 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Diesel Engines 5-27, 6-25 . . . . . . . . . . . . . . . . . . . . . . . . . .
Gasoline Engines 5-20, 6-23 . . . . . . . . . . . . . . . . . . . . . . . .
Crankcase Capacity 6-74 . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Cruise Control 2-36 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Customer Assistance for Text Telephone Users 8-3 . . . . . . . . .
Customer Assistance Information 8-1 . . . . . . . . . . . . . . . . . . .
Customer Satisfaction Procedure 8-2 . . . . . . . . . . . . . . . . . . . .
Damage
Finish 6-65 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Sheet Metal 6-64 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Daytime Running Lamps 2-44 . . . . . . . . . . . . . . . . . . . . . . . . .
Daytime Running Lamps Indicator Light 2-67 . . . . . . . . . . . .
Defects, Reporting Safety 8-6, 8-7 . . . . . . . . . . . . . . . . . . . . .
Defensive Driving 4-2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Defogging 3-6 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Diesel Engine Exhaust Brake 2-16 . . . . . . . . . . . . . . . . . . . . . .
Diff Lock Indicator Light 2-63 . . . . . . . . . . . . . . . . . . . . . . . . .
Do Not Shift Light 2-57 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Dome Lamps 2-46 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Door
Latches Check 7
-27 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Locks 2-4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Power Locks 2-4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Driver Position 1-11 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Driving
City 4
-19 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Defensive 4-2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Drunken 4
-3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Freeway 4-20 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
In a Blizzard 4-26 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
In Rain and on Wet Roads 4-16 . . . . . . . . . . . . . . . . . . . . . .
Night 4-15 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
On Curves 4-10 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
On Hill and Mountain Roads 4-22 . . . . . . . . . . . . . . . . . . . .
On Snow and Ice 4-24 . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Through Water 4-18 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Winter 4-24 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Drunken Driving 4-3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Electrical Equipment, Adding 6-68 . . . . . . . . . . . . . . . . . . . .
Electrical System 6-68 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Engine
Air Cleaner Filter 6
-77 . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Air Control 2-42 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Automatic Shutdown 2-11 . . . . . . . . . . . . . . . . . . . . . . . . . .
Coolant (Caterpillar
Diesel Engine) 6-27 . . . . . . . . . . . . .
Coolant (Gasoline Engine) 6-23 . . . . . . . . . . . . . . . . . . . . . .
Coolant Heater 2-15 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Coolant Level Check 7-23 . . . . . . . . . . . . . . . . . . . . . . . . . .
Coolant Temperature Gage 2-62 . . . . . . . . . . . . . . . . . . . . .
Cooling System Capacity 6-74 . . . . . . . . . . . . . . . . . . . . . . .
Crankcase Capacity 6-74 . . . . . . . . . . . . . . . . . . . . . . . . . . .
Diesel,Warm-Up 2-11 . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Exhaust 2-29, 2-30, 4-27 . . . . . . . . . . . . . . . . . . . . . . . . . . .
Fan Breakage 6-3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Fan Noise 5-33 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Fast Idle System 2-12 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
ProCarManuals.com