Propeller Shaft; Brakes; Brake Chamber Effective Area; Air System - PREVOST X3-45 COACH 2018 Operator's Manual

th
4 ............................................................... 1.000
th
5 ............................................................... 0.737
th
6 ............................................................... 0.639
Reverse ...................................................... 4.801
Converter........................................................ 1.9
Differential ratio (optional) ............................ 3.58

PROPELLER SHAFT

Hayes-Dana SPL250
provided with heavy-duty universal joints.

BRAKES

The features of the braking system include a
dual system where the front and rear circuits are
completely independent from each other. The
brakes are air operated disc type brakes with
automatic slack adjusters on front, drive and tag
axles. The emergency/parking
located on the drive and tag axles only.

BRAKE CHAMBER EFFECTIVE AREA

Front axle .................................................. 24 in
Drive axle .......... 24/24 in
Tag axle ............. 14/16 in

AIR SYSTEM

Compressed air is provided by a twin cylinder,
31.8 cfm Wabco, gear-driven, water-cooled and
engine oil lubricated air compressor.

ANTILOCK BRAKING SYSTEM (ABS)

The antilock braking system has one Electronic
Control Unit (ECU) controlling a four channel
system. A wheel slip sensor is mounted at each
front axle and drive axle wheel. The Tag axle
wheels are slave to the drive axle wheels.
The Electronic Control
maintenance free. Its operating voltage is 24 ±
6 volts DC. The thermal operating range for the
ECM is from -40 to 167°F (-40 to 75°C).
The solenoid control valves are maintenance
free. Their operating voltage is 24 (+4.8, -2.4)
volts DC. The rated current draw is 1.65 amps.
The thermal operating range of the solenoid
control valves is from -40 to 176°F (-40 to 80°C).

TROUBLESHOOTING AND TESTING

For troubleshooting and testing of the vehicle's
anti-lock braking system, refer to Meritor
WABCO Maintenance Manual: "Anti-Lock Brake
type tubular shafts,
brakes are
2
2
(service / emergency)
2
(service / emergency)
Module (ECM) is
PA1627 X3-45 Operator's Manual
Technical Information
Systems For Trucks, Tractors and Buses" or use
dashboard Driver Information Display (DID).
AUTOMATIC TRACTION CONTROL
(ATC) – ELECTRONIC STABILITY
PROGRAM (ESP)
In addition to the ABS function, vehicle may be
equipped with an advanced model of Bendix
EC-60 controller to provide an Automatic
Traction Control (ATC) feature. Bendix ATC
can improve vehicle traction during acceleration,
and lateral stability while accelerating through
curves. ATC utilizes Engine Torque Limiting
(ETL) where the ECU communicates with the
engine's controller and/or Differential Braking
(DB) where individual wheel brake applications
are used to improve vehicle traction.
The EC-60 advanced model controller also
provides ABS-based stability features referred to

as ESP Electronic Stability Program.
Refer to Maintenance Manual, Section 12: Brake
and Air System for more information on this
system.
CAUTION
Even with ESP-equipped vehicles, the driver
remains responsible for ensuring vehicle
stability during operation.
DANGER
ESP may reduce
automatically.
ESP can make the vehicle decelerate
automatically. ESP can slow the vehicle with
or without the operator applying the brake,
and even when the throttle is being applied.

STEERING


ZF 8098 integral hydraulic assisted steering
gear;

Variable assistance in function of speed is
optional.

Volvo hydraulic pump gear driven from
engine drive.

Hydraulic reservoir and dipstick accessible
from engine compartment.
9-7
the vehicle speed