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3. Store the seal in the inlet, located on the
underside of the hood
4. Store the clamp on the coolant surge tank.
Pull the overflow tube out of the white
plastic retainer, slip the clamp over and
reinstall the hose.
The seal will need to be replaced on to the air
cleaner for normal driving, especially in the
warmer months.
Automatic Transmission Fluid
When to Check
A good time to check your automatic transmission
fluid level is when the engine oil is checked.
See your Allison Automatic Transmission
Operator’s Manual to find out when to change
your transmission fluid and filters.
How to Check and What to Use
The Allison Automatic Transmission Operator’s
Manual that came with the vehicle shows how to
check the automatic transmission fluid and
what fluid to use.
Automatic Transmission External Filter
Your automatic transmission filter requires
periodic replacement.
Consult the Allison Automatic Transmission
Operator’s Manual that came with the vehicle for
proper change intervals.
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Manual Transmission Fluid
When to Check
A good time to have it checked is when the
engine oil is checked. Refer to the Maintenance
Schedule to find out when to check and change
your manual transmission fluid. SeeScheduled
Maintenance on page 363.
How to Check and What to Use
Check the fluid level only when your engine is off,
the vehicle is parked on a level place, and the
transmission is cool enough for you to rest
your fingers on the transmission case.
To check the transmission fluid level, do the
following:
1. Remove the filler plug.
2. Check to be sure that the lubricant level is up
to the bottom of the fill opening. On heavy
duty transmissions, an inch of oil level equals
about one gallon of fluid.3. If the fluid level is good, reinstall the plug and
be sure it is fully seated. If the fluid level is
low, add more fluid as described in the
next steps. Refer to the Maintenance
Schedule to determine what kind of fluid to
use. SeePart C: Recommended Fluids
and Lubricants on page 397.
How to Add Fluid
To add transmission fluid, do the following:
1. Remove the filler plug.
2. Add fluid at the filler plug hole. Add only
enough fluid to bring the fluid level up to
the bottom of the fill opening. Refer to
the Maintenance Schedule to determine the
proper fluid to use. SeePart C:
Recommended Fluids and Lubricants on
page 397.
3. Reinstall the filler plug. Be sure the plug is
fully seated.
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Electric Air Compressor
Your vehicle may have an electric air compressor.
This compressor is used to run options that
require pressurized air, such as an air horn, air
seat, 7.8L engine exhaust restrictor, or 7.8L engine
exhaust brake.
The air compressor is used when vehicles do not
have an air brake system.
The air supply for
this system must be
maintained by releasing
the drain valve to eject
any moisture that
may have built up in
the system.
It is recommended that this system be drained on
a weekly basis.
Clutch Pedal Free Travel
If you have a V8 engine and a manual
transmission, the clutch will need adjustment
when pedal free travel gets down to about 1/4 inch
(6 mm), as measured at the clutch pedal pad.
You should have 1 1/2 to 2 inches (38 to 51 mm)
of clutch pedal free travel.
If the clutch ever needs service, be sure to use
only GM clutch replacement parts.
Chassis Lubrication
Your Maintenance Schedule provides all of the
required chassis lubrication intervals and identifies
proper lubricants to use. Be sure to see the
Maintenance Schedule before performing any
chassis lubrication service. To determine location of
chassis lubrication items, use the following charts.
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Notice:Ignoring these steps could result in
costly damage to your vehicle that would
not be covered by your warranty.
Trying to start your vehicle by pushing or
pulling it will not work, and it could damage
your vehicle.
1. Check the other vehicle. It must have a
12-volt battery (or batteries) with a negative
ground system.
Notice:If the other vehicle’s system is not a
12-volt system with a negative ground,
both vehicles can be damaged. Only use
vehicles with 12-volt systems with negative
grounds to jump start your vehicle.
If you have a diesel engine vehicle with
two batteries (or more), you should know
before you begin that, especially in cold
weather, you may not be able to get enough
power from a single battery in another
vehicle to start your diesel engine.
If your vehicle has more than one battery, use
the one closest to the starter — this will
reduce electrical resistance.2. Get the vehicles close enough so the jumper
cables can reach, but be sure the vehicles are
not touching each other. If they are, it could
cause a ground connection you do not
want. You would not be able to start your
vehicle, and the bad grounding could damage
the electrical systems.
To avoid the possibility of the vehicles rolling,
set the parking brake firmly on both vehicles
involved in the jump start procedure. Put
an automatic transmission in PARK (P) or a
manual transmission in NEUTRAL before
setting the parking brake. If you have a
four-wheel-drive vehicle, be sure the transfer
case is in a drive gear, not in NEUTRAL.
Notice:If you leave your radio or other
accessories on during the jump starting
procedure, they could be damaged. The repairs
would not be covered by your warranty.
Always turn off your radio and other
accessories when jump starting your vehicle.
3. Turn off the ignition on both vehicles. Unplug
unnecessary accessories plugged into the
cigarette lighter or accessory power outlets.
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