freightliner Custom Classic MT45 2022, Руководство по обслуживанию

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32–00 Safety Precautions
Safety Precautions in this section apply to all
procedures within this group.
DANGER
When working on the vehicle, shut down the en-
gine or motor, set the parking brake, and chock
the tires. Before working under the vehicle, always
place jack stands under the frame rails to ensure
the vehicle cannot drop. Failure to follow these
steps could result in serious personal injury or
death.
32–01 Suspension Inspecting
Front and Rear Suspension
Spring Assemblies
Some reverse bow in the suspension leaf springs is
normal. Deflection in the springs is affected by the
carrying capacity of the spring package furnished
with the chassis and the load applied. If the springs
appear to bow considerably more than normal, have
a service dealer check for broken springs, or (con-
sider) adding a heavier spring package.
Rear Air Suspension
Follow the procedure below to determine if a pres-
sure drop in the rear air suspension system is within
the allowable range.
Air-Consuming Devices Turned Off
NOTE: With all air-consuming devices turned off
(service brakes released and parking brake ap-
plied [exhausted]), pressure drop must not ex-
ceed 2 psi (14 kPa) in one minute.
1. Park the vehicle on a level surface, place the
transmission in Neutral (N), and apply the park-
ing brake.
2. Turn off all air-consuming devices.
3. Run the engine until the air system reaches full
pressure.
NOTE: The minimum compressor cut-out pres-
sure is 110 psi (758 kPa).
4. Shut down the engine and wait one minute for
the air pressure to stabilize. Note the reading on
the air pressure gauge.
5. Wait one additional minute and check the gauge
reading again to see if there has been any pres-
sure drop.
6. Pressure drop from air leakage must be less
than 2 psi (14 kPa).
Air-Consuming Devices in Use
NOTE: With the service brakes applied and the
parking brake released (pressurized), pressure
drop must not exceed 3 psi (21 kPa) in one
minute.
1. Park the vehicle on a level surface, place the
transmission in Neutral (N), and chock the tires
to prevent the vehicle from rolling.
2. Turn off all air-consuming devices.
3. Run the engine until the air system reaches full
pressure.
NOTE: The minimum compressor cut-out pres-
sure is 110 psi (758 kPa).
4. Release the parking brake.
5. Shut down the engine, apply the brake pedal
fully, and wait one minute for the air pressure to
stabilize. Note the reading on the air pressure
gauge.
6. Wait one additional minute (with the brake pedal
fully applied) and check the gauge reading again
to see if there has been any pressure drop.
7. Pressure drop from air leakage must be less
than 3 psi (21 kPa).
32–02 Freightliner Suspension
Inspecting
Spring Front and Rear
Suspension Spring Assemblies
Inspection
Inspect the front and rear suspension spring assem-
blies for pitted, cracked, broken, or abnormally bent
leaves and extreme rust. If any of these conditions
exist, replace the spring assembly. See
Group 32 of
Suspension
32
Walk-In Van Chassis Maintenance Manual, July 2015
32/1