2-14
New Vehicle ªBreak-Inº
NOTICE:
Your vehicle doesn't need an elaborate
ªbreak
-in.º But it will perform better in the long
run if you follow these guidelines:
Let your engine warm up before you
operate your vehicle under load.
Keep your speed at 55 mph (88 km/h) or
less for the first 500 miles (805 km).
Don't drive at any one speed
-- fast or
slow
-- for the first 500 miles (805 km).
Don't make full
-throttle starts.
NOTICE: (Continued)
NOTICE: (Continued)
Avoid making hard stops for the first
200 miles (322 km) or so. During this time
your new brake linings aren't yet broken
in. Hard stops with new linings can mean
premature wear and earlier replacement.
Follow this breaking
-in guideline every
time you get new brake linings.
Use the lowest gear you can when you start
a loaded vehicle in motion and when going
up hills to avoid overloading the engine.
Check and adjust engine and transmission
fluid levels often and be sure tires are
properly inflated for the load you're
carrying.
If you have a Caterpillar
diesel engine, see
the Caterpillar Diesel Engine Operation
& Maintenance Manual.
2-17 Starting Your Engine
1. Without pushing the accelerator pedal, turn your
ignition key to START. When the engine starts, let
go of the key. The idle speed will go down as your
engine gets warm.
2. If the engine doesn't start in 10 seconds, push the
accelerator pedal all the way down and crank the
engine for five more seconds, unless it starts sooner.
3. If your engine still won't start (or starts but then
stops), it could be flooded with too much gasoline.
Wait 15 seconds to let the starter motor cool down.
Do Steps 1 through 3 again.
When the engine starts, let go of the key and the
accelerator pedal.NOTICE:
Your engine is designed to work with the
electronics in your vehicle. If you add electrical
parts or accessories, you could change the way
the engine operates. Before adding electrical
equipment, check with your dealer. If you don't,
your engine might not perform properly.
NOTICE:
If you ever need to have your vehicle towed, see
the part of this manual that tells how to do it
without damaging your vehicle. See ªTowing
Your Vehicleº in the Index.
2-18 Gasoline Engine Warm-Up
When you've started your engine, let it run for 20 or
30 seconds to warm up before you put a load on
the engine.
Drive at moderate speeds for the first few miles,
especially in cold weather. Running a cold engine at
high speed can damage it. See ªEngine High Idle
Systemº in the Index if your vehicle has this feature.
Restarting the Gasoline Engine While
Moving (Automatic Transmission)
If you have to restart the engine while the vehicle is
moving, you'll first have to shift the automatic
transmission to NEUTRAL (N). This safety feature
prevents starting the engine when the transmission is
in a drive gear.
Stopping the Gasoline Engine
Let your engine idle for a few seconds before turning it
off after you have finished driving your vehicle.
If you shift to NEUTRAL (N) or PARK (P), set the
parking brake.
If your vehicle has a two
-speed axle, put the range
selector in LOW. To be sure the axle has shifted into
LOW, engage the clutch and transmission; the vehicle
may move slightly when you do this.
While your engine is idling before you turn it off, you
can make a list of any operational or handling concerns
to give to responsible maintenance personnel so they can
handle them right away.
Moisture will condense in a fuel tank that is almost
empty if the engine has not run for a while, even just
overnight under some conditions. So, it's always best to
refuel your vehicle at the end of each run.
2-19
Starting the Diesel Engine
If you have a Caterpillar diesel engine, also refer to your
Caterpillar Diesel Engine Operation & Maintenance
Manual for starting procedure.
For vehicles with the DURAMAX diesel engine, also
see ªStarting Your DURAMAX Diesel Engineº
following.
To make starting easier in cold weather (below 32F or
0C), the proper viscosity engine oil should be used.
See ªEngine Oilº in the Index. It's also best to heat the
engine oil first. You can do this by using an engine
coolant heater.
NOTICE:
If you ever need to have your vehicle towed, see
the part of this manual that tells how to do it
without damaging your vehicle. See ªTowing
Your Vehicleº in the Index.
Restarting the Diesel Engine While Moving
(Automatic Transmission)
If you have to restart the engine while the vehicle is
moving, you'll first have to shift the automatic
transmission to NEUTRAL (N). This safety feature
prevents starting the engine when the transmission is
in a drive gear.
Stopping the Diesel Engine
If you have a Caterpillar diesel engine, see your
Caterpillar Diesel Engine Operation &
Maintenance Manual.
1. Set the parking brake and shift to NEUTRAL (N)
or PARK (P).
2. Turn the ignition key to OFF.
If your vehicle has a two
-speed axle, see ªRear Axle,
Tw o
-Speed Electric Shift Controlº or ªRear Axle,
Tw o
-Speed Airshift Controlº in the Index.
2-24
Starting Your DURAMAX
Diesel Engine
Your diesel engine starts differently than a
gasoline engine.
Automatic Transmission
Move your shift lever to PARK (P) or NEUTRAL (N).
Your engine won't start in any other position
-- that's
a safety feature. To restart when you're already moving,
use NEUTRAL (N) only.
NOTICE:
Don't try to shift to PARK (P) if your vehicle is
moving. If you do, you could damage the
transmission. Shift to PARK (P) only when your
vehicle is stopped.
Manual Transmission
Move your shift lever to neutral and hold the clutch
pedal to the floor while starting the engine. Your vehicle
won't start if the clutch pedal is not all the way
down
-- that's a safety feature.
Starting Your Engine
1. Turn your ignition key to RUN.
Observe the wait to start light. See ªWait To Start
Lightº in the Index. (This light may not come on
if the engine is hot.)
2. As soon as the wait to start light goes off,
IMMEDIATELY turn the ignition key to START.
When the engine starts, let go of the key.
NOTICE:
Holding your key in START for longer than
15 seconds at a time will cause your battery to be
drained much sooner. And the excessive heat can
damage your starter motor.
2-26 If Your Diesel Engine Won't Start
If you've run out of fuel, look at ªRunning Out of Fuel.º
See ªDiesel Fuel Requirements and Fuel Systemº in
the Index.
If you're not out of fuel, and your engine won't start,
do this:
Turn your ignition key to RUN. IMMEDIATELY
after the wait to start light goes off, 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 ªBatteryº in the owner's manual.
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.
Be sure you are using the proper fuel for existing
weather conditions. See ªDiesel Fuel Requirements and
Fuel Systemº in the Index.
If the engine starts, runs a short time, then stops, your
vehicle needs service.
CAUTION:
Do not use gasoline or starting ªaids,º such as
ether, in the air intake. They could damage your
engine. There could also be a fire, which could
cause serious personal injury.
2-27
Engine Checks Before Operating
When you've started your engine, let it run for 20 to
30 seconds before you put a load on the engine. But
don't leave the vehicle while the engine is running.
Avoid unnecessary idling of diesel engine equipped
vehicles.
If the engine idles too long, the temperature of the
engine coolant will fall below the normal operating
range. Low engine operating temperature causes several
conditions which affect engine operation and reduce
engine life.
The engine should be permitted to go through a
warm
-up period. Operate the vehicle at a minimum of
600 rpm during the warm
-up period. During this period
and during operation, the following observations should
be made.
During this warm
-up period, check your warning lights
and gages:
If oil pressure doesn't begin to rise within
15 seconds of starting, stop the engine and
find the cause.If the engine coolant temperature gage needle goes
into the hot area on the gage, stop the engine and
find the cause of the overheating.
If you have air brakes, the dual
-needle air pressure
gage should read at least 115 psi (790 kPa) for both
service systems before you try to move the vehicle.
When air pressure is below 60 psi (420 kPa), the
LOW AIR light will come on and you will hear a
tone alarm. If the pressure doesn't build up or
drops during warm
-up, stop the engine and find
the cause before you try to move the vehicle.
Recommended air pressure before actually driving
away is 120 psi (830 kPa).
The charging system light should come on when
the ignition key is turned to RUN or START and
should go out when the engine is running above idle.
If the light doesn't go out or comes back on during
normal engine operation, have the charging system
checked right away. (This light tells you if the
generator is not charging; it doesn't reflect the
condition of the battery.)
2-37 Eaton Fuller Five and Six-Speed
Transmissions and TTC Spicer
Seven-Speed Transmissions
These transmissions have gears that automatically
synchronize when you shift up or down (except
FIRST (1) gear on the five
-speed and seven-speed
transmission which is unsynchronized). Choose the gear
that will maintain the road speed you want while
keeping the engine above two
-thirds of the governed
speed. When the engine speed drops below two
-thirds of
the governed speed, shift into the next lower gear before
your engine begins to lug. When you shift down, be sure
to double
-clutch if required.
ZF Six-Speed Transmission
Here's how to operate
your transmission.
This six
-speed pattern is unique to GM manual
transmissions. The transmission always repositions
the shift lever to neutral, which is located between
FOURTH (4) and FIFTH (5) gear.
To prevent unintentional gear selections, additional
force is required to move the shift lever into
REVERSE (R) or FIRST (1). Use FIRST (1) when
trailer towing, driving with payload in the pickup box or
launching on a grade. Otherwise, start in SECOND (2)
gear. Only shift into FIRST (1) when the vehicle has
stopped moving.