1995 GMC SIERRA engine

How long should you keep the coolant heater plugged in? The answer
depends on the weather,
the kind of oil you have, and some other things.
Follow this chart.
Viscosity/
Oil Grade
SAE
1 OW-30
SAE
15W-40
32°F to 0°F
(0°C to -18°C)
Not
Required
Not
Required
0°F to -10°F
(-18OC
to
-23 O C)
Two
Hours:!:
Two
Hours‘%
Below -10°F
Below -23”
C
Eight Hours’>
or Overnight
Eight Hours* or Overnight
’%The times listed are minimum times.
It will not harm either the coolant
heater or the vehicle to leave
the coolant heater plugged in longer than the
times stated.
See “Diesel Fuel Requirements and Fuel System’’
in the Index for
information
on what fuel to use in cold weather.
If Your Diesel Engine Won’t Start
If you‘ve run out of fuel, look at “Running Out of Fuel” (see “Diesel Fuel
Requirements and Fuel System”
in the Index).
If you‘re not out of fuel, and your engine won’t start, do this:
Turn your ignition key to RUN. Make sure that the GLOW PLUGS light is
out. Then IMMEDIATELY turn the ignition key to START.
If the light doesn’t go off, wait a few seconds, then try starting your engine
again. And, see your dealer as soon as
you can for a starting system check.
If the light comes on and then goes off and you know your batteries are
charged, but your engine still won’t start, your vehicle needs service.
If the light does not come on when the engine is cold, your vehicle needs
service.
If your batteries don‘t have enough charge to start your engine, see
“Battery”
in the Index.
Be sure you have the right oil for your engine, and that you’ve changed the
oil at the proper times. If you use the wrong
oil, your engine may be harder
to start.
If the engine starts, runs a short time, then stops, your vehicle needs service.
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A CAUTION:
Do not use gasoline or starting “aids,” such as ether, in the air
intake. They could damage your engine. There could also be
a
fire, which could cause serious personal injury.
Engine Coolant Heater (Option)
In very cold weather. 0°F (-I SOC) or colder, the engine coolant heater can
help. You’ll get easier starting and better fuel economy during engine
warm-up. Usually, the coolant heater should
be plugged in a minimum of
four hours prior to starting your vehicle.
To use the coolant heater:
1. Turn off the engine.
2. Open the hood and unwrap the electrical cord.
3. Plug it into a normal, grounded I IO-volt outlet.
A CAUTION:
Plugging the cord into an ungrounded outlet could cause an
electrical shock. Also, the wrong kind
of extension cord could
overheat and cause
a fire. You could be seriously injured. Plug
the cord into
a properly grounded three-prong 110-volt outlet.
If the cord won’t reach, use a heavy-duty three-prong extension
cord rated for
at least 15 amps.
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NOTICE:
After you’ve used the coolant heater, be sure to store the cord as
it was before to keep
it away from moving engine parts. If you
don’t,
it could be damaged.
How long should you keep the coolant heater plugged in? The answer
depends on the weather, the kind of oil you have. and some other things.
Inste.ad of trying
to list everything here, we ask that you contact your GM
dealer in the area where you‘ll be parking your vehicle. The dealer can give
you the best advice for that particular area.
Automatic Transmission
There are several different positions for your shift lever.
If your vehicle is equipped with an automatic transmission, it now features
an electronic shift position indicator
within the instrument cluster. This
display must be powered anytime the shift lever is capable
of being moved
out of the
PARK (P) position. This means that if your key is in the OFF
position, but not locked, there will be a small current drain on your battery
which could discharge your battery over
a period of time. If you have a need
to leave your key
in the ignition in the OFF position for an extended period
for any reason,
it is recommended that you disconnect the battery cable
from the battery to prevent discharging your battery.
PARK (P) -This locks your rear wheels. It’s the best position to use
when you start your engine because your vehicle can’t move easily.
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Your vehicle has a brake-transmission shift interlock. With the ignition in
the RUN position, you must fully apply your regular brakes before you can
shift from PARK (P).
If you cannot shift out of PARK (P), ease pressure on the shift lever and
push the
shift lever all the way into PARK (P) as you continue pressing the
brake pedal.
Then move the shift lever into the gear you want. If you still
cannot shift the shift lever out of
PARK (P), see ”Shifting Out of PARK (P)”
later in this section.
REVERSE (R) - Use this gear to back up.
NOTICE:
Shifting to REVERSE (R) while your vehicle is moving forward
could damage your transmission. Shift to REVERSE
(R) only
after your vehicle is stopped.
To rock your vehicle back and forth to get out of snow, ice or sand
without damaging your transmission, see
“If You‘re Stuck: In Sand,
Mud, Ice or Snow”
in the Index.
a NEUTRAL (N) - In this position, your engine doesn’t connect with
the wheels. To restart when you’re already moving, use NEUTRAL (N)
only. Also, use NEUTRAL (N) when your vehicle is being towed.
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A CAUTION:
Shifting out of PARK (f) or NEUTRAL (N) while your engine is
“racing” (running at high speed) is dangerous. Unless your foot
is firmly on the brake pedal, your vehicle could move very
rapidly.
You could lose control and hit people or objects. Don’t
shift out of
PARK (P) or NEUTRAL (N) while your engine is
racing.
NOTICE:
Damage to your transmission caused by shifting out of PARK
(P) or NEUTRAL (N) with the engine racing isn’t covered by
your warranty.
AUTOMATIC OVERDRIVE (a) - This position is for normal
driving. If you need more power for passing, and you’re:
- Going less than about 35 mph (56 km/h), push your accelerator
pedal about halfway down.
the way down.
You’ll shift down to the next gear and have more power.
- Going about 35 mph (56 kdh) or more, push the accelerator all
0 should not be used when towing a trailer, carrying a heavy load,
driving on steep hills, or for off-road driving. Select THIRD
GEAR
(3) when operating the vehicle under any of these
conditions.
THIRD GEAR (3) - This is like 63, but you never go into Overdrive.
You should use
THIRD GEAR (3) when towing a trailer. carrying a
heavy load, driving on steep hills, or
for off-road driving.
0 SECOND GEAR (2) - This position gives you more power but lower
fuel economy. You can use
SECOND GEAR (2) on hills. It can help
control
your speed as you go down steep mountain roads, but then you
would also want
to use your brakes off and on.
If you manually select SECOND GEAR (2), the transmission will drive
in second gear. You may use this feature for reducing torque to the rear
wheels when you are trying
to start your vehicle from a stop on
slippery road surfaces.
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You can shift into FIRST GEAR (2) when you’re going less than 20
mph (32 kmh). If you’ve come to a complete stop and it’s hard to shift
into FIRST GEAR
(2), put the shift lever in NEUTRAL (N) and let up
on the clutch. Press the clutch pedal back down. Then shift into FIRST
GEAR
(2). If you try to shift into FIRST GEAR (2) at excessive
vehicle speeds, the shift lever will not move into the FIRST GEAR
(2)
position until vehicle speed is reduced.
0 SECOND GEAR (3) - Press the clutch pedal as you let up on the
accelerator pedal and shift into SECOND GEAR
(3). Then, slowly let
up on the clutch pedal as you press
the accelerator pedal.
0 THIRD GEAR (4), FOURTH GEAR (5) - Shift into the higher
forward gears
the same way you do for SECOND GEAR (3). Slowly
let up on the clutch pedal as you press the accelerator pedal.
To Stop - Let up on the accelerator pedal and press the brake pedal.
Just before
the vehicle stops, press the clutch pedal and the brake pedal,
and shift to NEUTRAL
(N).
NEUTRAL (N) - Use this position when you start or idle your
engine.
REVERSE (R) - To back up, first press down the clutch pedal. Wait
about
5 seconds for the internal parts to stop spinning and then, shift
into REVERSE (R). Let up
on the clutch pedal slowly while pressing
the accelerator pedal.
NOTICE:
Shift to REVERSE (R) only after your vehicle is stopped.
Shifting to
REVERSE (R) while your vehicle is moving could
damage your transmission.
Also, use REVERSE (R), along with the parking brake, when turning
off your engine and parking your vehicle.
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Five Speed Manual Transmission (Without
Low Gear)
6 If you have a five
speed manual
transmission without
low gear
(RPO MG5),
this is your shift
pattern. Here’s how to
operate your
transmission:
FIRST GEAR (1) - Press the clutch pedal and shift into FIRST
GEAR
(1). Then, slowly let up on the clutch pedal as you press the
accelerator pedal.
You can shift into FIRST GEAR (1 ) when you’re going less than 20
mph (32 kdh). If you’ve come to a complete stop and it‘s hard to shift
into FIRST GEAR
(1). put the shift lever in NEUTRAL (N) and let up
on the clutch. Press the clutch pedal back down. Then shift into FIRST
GEAR
(1).
SECOND GEAR (2) - Press the clutch pedal as you let up on the
accelerator pedal and shift into SECOND GEAR
(2). Then, slowly let
up
on the clutch pedal as you press the accelerator pedal.
THIRD GEAR (3), FOURTH GEAR (4) and FIFTH GEAR (5) -
Shift into THIRD GEAR (3). FOURTH GEAR (4) and FIFTH GEAR
(5) the same way you do for SECOND GEAR (2). Slowly let up on the
clutch pedal
as you press the accelerator pedal.
Just before the vehicle stops, press the clutch pedal and the brake pedal,
and shift to NEUTRAL
(N).
0 To Stop - Let up on the accelerator pedal and press the brake pedal.
NEUTRAL (N) - Use this position when you start or idle your
engine.
REVERSE (R) - To back up, first press down the clutch pedal. Wait
about 5 seconds for the internal parts to stop spinning and then, shift
into REVERSE (R). Let up on the clutch pedal slowly while pressing
the accelerator pedal.
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NOTICE:
Shift to REVERSE (R) only after your vehicle is stopped.
Shifting to REVERSE
(R) while your vehicle is moving could
damage
your transmission.
Also, use REVERSE (R), along with the parking brake, when turning
off your engine and parking your vehicle.
SHIFT Light
If you have a manual
transmission, you may
have
a SHIFT light.
This light will show
you when
to shift to
the
next higher gear
for best
fuel economy.
When this light comes on, you can shift to the
next higher gear if weather,
road and traffic conditions let you.
For the best fuel economy, accelerate
slowly and shift when the light comes on.
While you accelerate,
it is normal for the light to go on and off if you
quickly change the position of the accelerator. Ignore the
SHIFT light when
you downshift.
Four-wheel Drive Vehicles Only: If your vehicle has four-wheel drive
and is equipped with a manual transmission, disregard the
SHIFT light
when
the transfer case is in 4-LOW.
Manual Transmission Shift Speeds
If you have a five speed manual transmission with low gear (RPO MW3)
and one of the following engines, this chart shows when to shift to the next
higher gear for best fuel economy.
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