1993 GMC SIERRA engine

Featums & Contmls
R (Reverse)
Use this gear to back up.
Shifting
to R (Reverse) while your vehicle is moving forward could damage
your transmission. Shift
to R (Reverse) only after your vehicle is stopped. I
b
1
damaging your transmission, see “If Yo$re Stuck: In Sand, Mud, Ice or
Snow” in the Index.
N (Neutral)
In this position, your engine doesn’t connect with the wheels.
To restart when
you’re already moving, use
N (Neutral) only. Also, use N (Neutral) when your
vehicle is being towed.
CAUTION I
Shifting out of P (Park) or N (Neutral) while your engine is “racing”
(running at high speed) is dangerous. Unless your foot is fi\
rmly on
the brake pedal, your vehicle could move very rapidly. You cou\
ld lose
control and hit people
or objects. Don’t shift out of P (Park) or N
wI ! your enaine is racing.
I
NOTICE
I
1
Damage to your transmission caused by shifting out of P (Park) or N
(Neutral) with the engine racing isn’t covered by your war\
ranty.
OD (Automatic Overdrive)
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
- Going about 35 mph (56 kmlh) or more, push the accelerator all the
pedal about halfway down
way down
You’ll shift down
to the next gear and have more power.
OD should not be used when towing a trailer, carrying a heavy load, driving
on steep hills,
or for off-road driving. Select D (third gear) when operating the
vehicle under any of these conditions.
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2 (Second Gear)-Press the clutch pedal as you let up on the
accelerator pedal and shift into
2. Then, slowly let up on the clutch
pedal as you press the accelerator pedal.
3, 4 and 5 (Third, Fourth and Fifth Gears)-Shift into 3, 4 and 5 the
same way you do for
2. 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)-Use this position when you start or idle your engine,
R (Reverse)-To back up, press down the clutch pedal and shift into R. Let
up on the clutch pedal slowly while pressing the accelerator p\
edal.
Shift to
R (Reverse) only after your vehicle is stopped. Shifting to R
(Reverse) while your vehicle is moving could damage your transmission
Also, use Reverse, along with the parking brake, for parking your vehicle.
FivemSpeed Manual 7Fansmission
(With Low Gear)
e
K2464
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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
N (Neutral).
N (Neutral)-Use this position when you start or idle your engine.
R (Reverse)-To back up, press the clutch pedal and shift into R. Let up on
the clutch pedal slowly while pressing the accelerator pedal. If you shift from
OD into R, the shift lever must first be placed in the N (Neutral) position
centered between
2 and 3 prior to shifting into R.
NOTICE I
Shift to R (Reverse) only after your vehicle is stopped. Shifting to R
(Reverse) while vour vehicle is movina could damaae vour transmission.
- -
Also, use Reverse, along with the parking brake, for parking your ve\
hicle.
Shift Light
I K2317
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.
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Features & Controls
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.
Shift Speeds-Manual Transmission
This chart shows when to shift to the next higher gear for best fuel economy.
MANUAL TRANSMISSION RECOMMENDED SHIFT SPEED
IN MPH (KMIH)
Engine
and
VIN
45-50 25-40 50 40 15
4,3L
V6
3 to 4 2 to 3 1 to 2 3 to 4 2 to 3 1 to 2 Code
Trans. Cruise Shift Speed
Acceleration Shift Speed
(4
- (64) (40) (24) (K)
(72-80)
(40-64) - (80) (64)
(24)
5-Speed*
40 25 15 5.7L V8
- -
* Transmission with L (low) gear only. L (low) is intended for heavy loads and
is not recommended for normal driving.
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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 smoothly or for good
performance.
I A If you skip more than one gear when you downshift, you could lose
I & control of your vehicle: And you could injure yourself or others. I
I Ju skip more than one gear when you downshift, or if you race the
;,,,ine when you downshift, you can damage the clutch or transmission. \
I
Locking Rear Axle
If you have this feature, your rear axle can give you additional \
traction on
snow, mud, ice, sand or gravel.
It works like a standard axle most of the
time,
but when one of the rear wheels has no traction and the other does,
the locking feature
will allow the wheel with traction to move the vehicle.
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Features & Controls
Propshaft Brake Burnish Procedure
If you have a 3500 HD Model, it is recommended that the propshaft mounted
parking brake be burnished as part of the new vehicle break in. The parking
brake
will work best after it has been burnished following these instructions.
Make
10 stops, using the parking brake foot pedal, from 20 mph (32 k\
m/h)
about 2
112 miles (4 km) apart. In between stops, drive the vehicle at 20
mph (32 kmlh).
Torque Lock
The parking brake should be set first whenever leaving the dri\
ver’s seat. If
you are parked on a hill and the transmission is placed in P (Park) before
the parking brake is set, the weight of the vehicle may put too much force
on the parking pawl in the transmission.
It may be difficult to pull the selector
lever out of
P (Park). This is called “torque lock.” To prevent this, the parking
brake should be set
BEFORE moving the selector lever to P (Park).
When preparing
to move the vehicle, the selector lever should be moved out
of
P (Park) BEFORE releasing the parking brake. Set the parking brake first,
then release the transmission from
P (Park), even on level surfaces.
If “torque lock” does occur, you may have to have another vehicle nudge
your vehicle uphill a little
to take some of the pressure off the transmission
while you pull the selector lever out of
P (Park).
Shifting Into P (Park) (Automatic Transmission Models Only)
1 CAUTION
It can be dangerous to get out of your vehicle if the shift lever is not
fully in
P (Park) with the parking brake firmly set. Your vehicle can
roll.
If you have left the engine running, the vehicle can move suddenly.
You
or others could be injured. TO be sure your vehicle won’t move,
when you’re
on fairly level ground, use the steps that follow.
If you have four-wheel drive and your transfer case is in N (Neutral),
your vehicle will be free to roll-even if your shift lever is in P
{Park). So, be sure the transfer case is in a drive gear-not N
(Neutral).
If you are parking on a hill, or if you’re pulling a trailer, also see
“Parking on Hills9’ or “Towing a Trailer” in the Index. I
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Leaving Your Vehicle With the Engine Running (Automatic
Transmission Models Only)
I CAUTION
A It can be dangerous to leave your vehicle with the engine running. 1
1 Your vehicle could move suddenly if the shift lever is not fully in P
(Park) with the parking brake firmly set.
If you have a four-wheel drive with a manual transfer case sh\
ift lever
and your transfer case
is in N (Neutral), your vehicle will be free to
roll, even
if your shift lever is in P (Park). So be sure the transfer
case is in a drive gear-not in
N (Neutral).
And,
if you leave the vehicle with the engine running, it could
overheat and even catch fire. You or others could be injured. Don’t
leave your vehicle with the engine running unless you have to.\

If you have to leave your vehicle with the engine running, be su\
re your
vehicle
is in P (Park) and your parking brake is firmly set, before you leav\
e
it. If you have a four-wheel drive, be sure that the transfer case i\
s in a drive
gear-not in
N (Neutral).
After you’ve moved the shift lever into the
P (Park) position, hold the regular
brake pedal down. Then, see
if you can move the shift lever away from P
(Park) without first pulling it toward you.
If you can, it means that the shift lever wasn’t fully locked into
P (Park).
Parking Your Vehicle (Manual Transmission Models Only)
Before you get out of your vehicle, put your manual transmission in R
(Reverse) and firmly apply the parking brake.
If you have four-wheel drive, be sure your transfer case is in a\
drive gear.
Your vehicle could roll
if it isn’t.
If you are parking on a hill, or if your vehicle is equipped to tow a trailer,
see “Parking on Hills” or “Towing a Trailer” in the\
Index.
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Featums & Contds
Engine Exhaust
d th. .-
Y t hr--- 'xhaust coming in if:
-
- Your vehicle sets rusty underneath.
* Your vehicle was damaged in a collision.
- Your vehicle was damaged when driving over high points on .Ik
Your exhaust system sounds strange or
road or over road debris. iii$!,
Repairs weren't done correctly. - ' : -.- n, .'. .! .*: 3.:*-;
Your vehicle or exhaust system had bee; modified improp&,
Drive it only with all the windows down to blow out any CO; l
Have it fixed immediately I
.. .lI : .. : --.,
If you ever suspect exhaust is coming into your vehicle:
and
I
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Running Your Engine While You%
Parked [Automatic mansmission)
It’s better not to park with the engine running. But if you ever have to, here
are some things
to know.
1 CAUTION I
* Idling the engine with the air system control off could allow
‘ jangerous exhaust into your vehicle. (See the earlier Caution under
**A :E ..:i *; !.< .. 5;:. ::.; ,$+ : ‘Engine Exhaust”.) ~~-?~c-~~~~~=~~:-
Also, Idling in a closed-in place can let deadly oxide (CO)
nto your vehicle, even if the fan switch is at the highest setting. One
place this can happen
is a garage. Exhaust-with co--( -% -c ?& 2asily. NEVER park in a garage with the engine runni
?-! 4nother ,I: -‘i closed-in place can be a blizzard. (See “Blizzard“ in th
Index.)
CAUTION
It can be dangerous to get out of your vehicle if the shift lever is not
L fully in P (Park) with the parking brake firmly set. Your vehicle can
roll. Don’t leave your vehicle when the engine is running unless
you
have to. If you’ve left the engine running, the vehicle can move
suddenly. You
or others could be injured. To be sure your vehicle
won’t move, even when you’re on fairly level ground,, alw\
ays
set your
parking brake and move the shift lever to
P (Park).
I
If you have four-wheel drive and your transfer case is in N (Neutral},
your vehicle
will be free to roll, even if your shift lever is in P (Park),
So, be sure the transfer case is in a drive gear-not in N (Neutral).
Foliow the proper -steps to be sure your vehicle won’t move. -See
“Shifting Into P (Park)” in the Index.
If you are parking on a hill, or if you’re pulling- -a- trailer, also see
“Parking on Hilis”-.or “Towing -a Trailer”‘ in the Index.
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