1994 GMC SIERRA fuel

Manual Transmissions- Shift Speeds
If you have a five-speed manual transmission (with low gear), th\
is chart
shows when to shift to the next higher gear for best fuel economy.
Recommended Shift Speeds - Five Speed
Manual Transmission
with Low Gear*
Engine (VIN Code)
4.3L V6 (Z)
5.7L V8 (K)
4.3L V6 (Z)
Acceleration Shift Speed MPH (KM/H)
15 (24)
15 (24) 40 (64)
25 (40)
Cruise Shift Speed MPH (KM/H)
25-40
(40-64) 50
(80)
40 (64)
45-50
(72-80)
*L (low) is intended for use with heavy loads and is not recommended for
normal driving
If your speed drops below
20 mph (32 km/h), or if the engine is not running
smoothly, you should downshift to the next lower gear. You may have to
downshift two or more gears to keep the engine running smoothl\
y or for
good performance.
NOTICE:
If you skip more than one gear when you downshift, or if you
race the engine when you downshift, you can damage the engine,\

clutch or transmission.
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When your headlights or parking lights are on, rotate the dial to the right of
your headlight switch up
to brighten, or down to dim, your transfer case
indicator light.
2H (2-Wheel High): This setting is for driving in most street and highway
situations. Your front axle is not engaged
in two-wheel drive.
4H (4-Wheel High): This setting engages your front axle to help drive your
vehicle. Use
4H when you need extra traction, such as on wet or icy roads,
or in most off-road situations.
N (Neutral): Shift to this setting only when your vehicle needs to be towed
or when using a power take-off.
4L (4-Wheel Low): This setting also engages your front axle to give you
extra power, but should be used only for off-road driving.
You can shift from
2H to 4H or from 4H to 2H while the vehicle is moving.
Your front axle will engage faster if you take your foot off of the accelerator
for a few seconds after you shift.
In extremely cold weather it may be
necessary to stop or slow the vehicle to shift
out of 2H.
To shift into or out of 4L or “N” (Neutral):
Slow the vehicle to a roll, about 1-3 mph (2-5 kdh) and shift your
transmission into neutral.
0 Shift the transfer case shift lever in one continuous motion.
Don’t pause
in “N” (Neutral) as you shift the transfer case into 4L, or your
gears could clash.
Remember that driving
in 4H or 4L may reduce fuel economy. Also, driving
in four-wheel drive on dry pavement could cause your tires to wear fdster
and make your transfer case harder to shift.
Front Axle Locking Feature
The front axle locks and unlocks automatically when you shift the transfer
case. Some delay
for the axle to lock or unlock is normal. If the outside
temperature is very hot, or the vehicle has been used under hard driving
conditions, there may be
a slight delay for the axle to unlock.
Whenever you are
in four wheel drive, the rear wheel anti-lock brake
system does not operate. The regular brake system operates normally. When
you shift back into two-wheel drive, the anti-lock brake system will
operate.
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lnstument Panel
1 23 456 7093 10 3 1
17 1.6
15 14
13 12
I. Side Window Defogger Vents
2. Light Controls
3. Air Vents
4. Multifunction Lever
5. Tilt Lever
6. Instrument Cluster
7. Gearshift Lever
8. Audio System
9. Comfort Control System
11
10. Glove Box
1 1. Audio System
12. Ashtray
13. Rear Window Defogger Switch
14. Air Vent Handles
15. Cargo Lamp Switch or Dome
Light Override Switch
16. Fuse Panel
17. Parking Brake Release Handle
lnstrument Cluster
Your instrument cluster is designed to let you know at a glance how your
vehicle is running. You’ll know
how fast you’re going, about how much
fuel you have and many other things you’ll need
to know to drive safely and
economically.
Tachometer Cluster
If you have the tachometer cluster, it looks different but will tell you
everything the standard cluster does, with
the addition of displaying your
engine’s revolutions per minute (rpm).
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A CAUTION:
The brake system warning light will also come on when you set your
parking brake, and
it will stay on if your parking brake doesn’t release fully.
If it stays on after your parking brake is fully released, it means you have a
brake problem.
Water in Fuel Light
The red Water in Fuel
light,
if you have one,
is located near the
middle right edge of
the instrument cluster,
just below the turn
signal and lane change
indicator.
This light will come on to warn you
if there is water in the diesel fuel
system. For more information on how this light works, see “Diesel Fuel
Requirements and Fuel System”
in the Index.
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Malfunction Indicator (Service Engine Soon) Lamp
The orange
SERVICE
ENGINE
SOON
A computer monitors the operation of your fuel, ignition and emission
control systems. This light should come on when the ignition
is on but the
engine is not running,
as a check to show you its working. If it does not
come
on at all, have it fixed right away. If it stays on, or comes on while you
are driving, the computer is indicating that you have a problem. You should
take your vehicle in for service soon.
NOTICE:
If you keep driving your vehicle with this light on, after a while
the emission controls won’t work
as well, your fuel economy
won’t be as good, and your engine may not run as smoothly.
This could lead to costly repairs not covered by your warranty.
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Shift Indicator Light
The orange SHIFT
Indicator light, if you
have one,
is located
near the upper left
corner of the
instrument cluster.
This light, with the word
SHIFT and the upshift arrow, is used on some
models with manual transmissions. Depending on your particular model,
your vehicle may
not have this light. The SHIFT indicator light will help
you get the best fuel economy. See “Shift Light” or “Shift Speeds-
Vehicles Without Shift Light”
in this section for more information.
Headlight High Beam Indicator Light
light is located near
the middle left edge of
the instrument cluster.
The high beam indicator
is on whenever you use your high beam headlights.
For more details about high beams, see “Headlight High-Low Beam”
earlier
in this section.
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Gages
Fuel Gage
Standard Cluster -Gas Standard Cluster --Diesel
Tachometer Cluster -Gas Tachometer Cluster --Diesel
The fuel gage, when the ignition is on. tclls you about how much fuel you
have left
in your tank. The gage will first indicate empty before you are out
of fuel, and you should get Inore fuel as soon 11s possiblc.
Listed are four situations you may experience
with your fuel gage:
At the gas station. the fuel pump shuts off before the gage reads full.
0 It takes a little more or less fuel to fill up than thc I’wI gage indicated.
For example, the gage may have indicatcd thc tank was half full. but it
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actually took a little more or less than half the tank’s capacity to fill the
tank.
The gage moves a little when you turn a corner or speed up.
The gage doesn’t go back to empty when you turn off the ignition.
None of these indicate a problem with
the fuel gage.
For information on how to
fill your fuel tank, see “Fuel - Filling Your
Tank”
in the Index.
For your fuel tank capacity, see
“Fuel --Tank Capacity” in the Index.
Engine Coolant Temperature Gage
This gage shows the engine coolant temperature. If the gage pointer moves
into the red area, about
260” F ( 145” C) or more, your engine is too hot! It
means that your engine coolant has overheated. If you have been operating
your vehicle under normal operating conditions, you should pull off the
road, stop
your vehicle, and turn off the engine as soon as possible.
Hot Cooianf Can Burn You Badly!
In “Problems on the Road,” this ~nanual shows what to do. See “Engine
Overheating”
in the Index.
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