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School Bus Product

Overview

A school bus is a purpose-built pupil-transport vehicle defined less by its driveline than by the safety standards wrapped around it. The familiar Type C — engine ahead of the entry door on a cowl chassis — uses body-on-frame construction: a steel passenger body bolted onto a separate ladder frame, which lets the same chassis serve many body lengths. National standards govern the seat spacing, the steel side structure with rub rails, the rollover strength, the flashing-light sequence, and the swing-out stop arm, all aimed at one goal — protecting children who are too young to protect themselves. The result is among the safest vehicles on the road per passenger-mile.

How it works

The bus runs on a conventional diesel driveline: the Diesel Engine, a turbocharged inline-six with common-rail injection cooled by a front radiator and pump, drives through the Transmission to the Drive Axle and its dual rear wheels. Multi-leaf Suspension smooths the ride under a full load, and full Air Brakes with discs at every wheel stop it. The whole drivetrain and body sit on the Body-on-Frame Chassis.

Above the frame, the Body Shell is the riveted steel cage that gives the bus its strength, carrying the rub rails, drop-sash windows, and folding entry door. Inside, the Seating uses high-back padded benches whose close spacing "compartmentalises" passengers so a child is cushioned in a crash without a belt. The Safety System is the visible difference from any other bus: a Stop Arm swings out and Warning Lights flash amber then red to halt surrounding traffic while children load, with emergency exits and a front crossing gate. The driver works from the Driver Area through hydraulically assisted Steering, the HVAC system keeps the cabin warm, and a high-output Electrical System system powers the heavy warning-light load from batteries kept charged by the alternator.

Build & assembly graph

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Bill of materials

15 top-level lines · 107 rows shown · 385 parts total · indented to 3 levels
# Item / sub-assembly Part no. Qty/assy Ext. qty Parts Type
1 Body-on-Frame Chassis 3 parts school-bus-chassis 1 11 assembly
1.1 Frame Rail (C-channel) school-bus-frame-rail 2 part
1.2 Crossmember school-bus-crossmember 8 part
1.3 Fastener Set fastener-set 1 part
2 Diesel Engine 8 parts school-bus-diesel-engine 1 23 assembly
2.1 Engine Block & Head school-bus-engine-block 1 part
2.2 Piston & Rod school-bus-piston 6 part
2.3 Crankshaft school-bus-crankshaft 1 part
2.4 Turbocharger school-bus-turbo 1 part
2.5 Common-Rail Injection 3 parts school-bus-fuel-injection 1 8 assembly
2.5.1 Fuel Injector school-bus-injector 6 part
2.5.2 High-Pressure Fuel Pump school-bus-hp-pump 1 part
2.5.3 Common Fuel Rail school-bus-fuel-rail 1 part
2.6 Radiator radiator 1 part
2.7 Coolant Pump coolant-pump 1 part
2.8 Oil Seal oil-seal 4 part
3 Transmission 5 parts school-bus-transmission 1 17 assembly
3.1 Helical Gear Pair gear-pair 6 part
3.2 Gearbox Housing gearbox-housing 1 part
3.3 Ball Bearing ball-bearing 6 part
3.4 Oil Seal oil-seal 3 part
3.5 Torque Converter school-bus-torque-converter 1 part
4 Drive Axle 5 parts school-bus-drive-axle 1 17 assembly
4.1 Open Differential 4 parts differential 1 6 assembly
4.1.1 Differential Case diff-case 1 part
4.1.2 Side Gear side-gear 2 part
4.1.3 Pinion Gear pinion-gear 2 part
4.1.4 Cross Pin cross-pin 1 part
4.2 Axle Housing school-bus-axle-housing 1 part
4.3 Axle Shaft school-bus-axle-shaft 2 part
4.4 Ball Bearing ball-bearing 4 part
4.5 Oil Seal oil-seal 4 part
5 Suspension 2 parts school-bus-suspension 1 8 assembly
5.1 Leaf Spring leaf-spring 4 part
5.2 Shock Absorber school-bus-shock 4 part
6 Air Brakes 5 parts school-bus-air-brakes 1 16 assembly
6.1 Brake Disc (rotor) brake-disc 6 part
6.2 Brake Chamber school-bus-brake-chamber 6 part
6.3 Air Compressor school-bus-air-compressor 1 part
6.4 Air Reservoir Tank school-bus-air-tank 2 part
6.5 Treadle Valve school-bus-treadle-valve 1 part
7 Wheel Assembly 5 parts wheel-assembly 6 9 assembly
7.1 Alloy Wheel alloy-wheel 6 part
7.2 Tire tire 6 part
7.3 TPMS Sensor tpms-sensor 6 part
7.4 Lug Nut lug-nut 30 part
7.5 Valve Stem valve-stem 6 part
8 Body Shell 7 parts school-bus-body-shell 1 27 assembly
8.1 Floor Structure school-bus-floor 1 part
8.2 Side Panel school-bus-side-panel 2 part
8.3 Roof Bow school-bus-roof-bow 6 part
8.4 Rub Rail school-bus-rub-rail 4 part
8.5 Entry Door school-bus-entry-door 1 part
8.6 Side Window school-bus-window 12× 12 part
8.7 Fastener Set fastener-set 1 part
9 Seating 2 parts school-bus-seating 1 104 assembly
9.1 Seat Assembly 5 parts seat-assembly 13× 13 7 assembly
9.1.1 Seat Frame seat-frame 13 part
9.1.2 Seat Foam seat-foam 26 part
9.1.3 Seat Cover seat-cover 13 part
9.1.4 Seat Motor seat-motor 26 part
9.1.5 Seat Heater Mat seat-heater 13 part
9.2 Seat Frame school-bus-seat-frame 13× 13 part
10 Safety System 4 parts school-bus-safety-system 1 18 assembly
10.1 Stop Arm 3 parts school-bus-stop-arm 1 3 assembly
10.1.1 Stop Sign Blade school-bus-stop-sign 1 part
10.1.2 Stop Arm Actuator school-bus-stop-actuator 1 part
10.1.3 Relay relay 1 part
10.2 Warning Lights 3 parts school-bus-warning-lights 1 11 assembly
10.2.1 Warning Lamp school-bus-warning-lamp 8 part
10.2.2 Relay relay 2 part
10.2.3 Flasher Module school-bus-flasher-module 1 part
10.3 Emergency Exit school-bus-emergency-exit 3 part
10.4 Crossing Gate school-bus-crossing-gate 1 part
11 Steering 4 parts school-bus-steering 1 5 assembly
11.1 Steering Gear school-bus-steering-gear 1 part
11.2 Steering Column school-bus-steering-column 1 part
11.3 Power Steering Pump school-bus-power-steering-pump 1 part
11.4 Ball Bearing ball-bearing 2 part
12 Driver Area 3 parts school-bus-cab 1 11 assembly
12.1 Seat Assembly 5 parts seat-assembly 1 7 assembly
12.1.1 Seat Frame seat-frame 1 part
12.1.2 Seat Foam seat-foam 2 part
12.1.3 Seat Cover seat-cover 1 part
12.1.4 Seat Motor seat-motor 2 part
12.1.5 Seat Heater Mat seat-heater 1 part
12.2 Dashboard 3 parts school-bus-dashboard 1 3 assembly
12.2.1 LCD Panel lcd-panel 1 part
12.2.2 Microcontroller mcu 1 part
12.2.3 Switch Panel school-bus-switch-panel 1 part
12.3 Windshield school-bus-windshield 1 part
13 HVAC 3 parts school-bus-hvac 1 5 assembly
13.1 Heating Element heating-element 2 part
13.2 Blower Motor school-bus-blower 2 part
13.3 HVAC Duct school-bus-hvac-duct 1 part
14 Electrical System 3 parts school-bus-electrical 1 68 assembly
14.1 12 V Battery lv-battery 2 part
14.2 Alternator 4 parts school-bus-alternator 1 25 assembly
14.2.1 Stator Assembly 3 parts + deeper › stator-assembly 1 3 assembly
14.2.2 Rotor Assembly 4 parts + deeper › rotor-assembly 1 19 assembly
14.2.3 Rectifier & Regulator school-bus-rectifier 1 part
14.2.4 Ball Bearing ball-bearing 2 part
14.3 Wiring Harness 3 parts school-bus-harness 1 41 assembly
14.3.1 Wire Bundle wire-bundle 1 part
14.3.2 Connector connector 30× 30 part
14.3.3 Relay relay 10× 10 part
15 Fuel Tank school-bus-fuel-tank 1 part

Sourcing — likely vendors

Companies that make this · indicative price $8k–$90k · MOQ & lead are typical
VendorHQSpecialtyMOQLead time
🇯🇵Toyota
global.toyota ↗
Toyota City, JP Automaker made to order 16–28 wks
volkswagen-group.com ↗ Wolfsburg, DE Automaker made to order 16–28 wks
gm.com ↗ Detroit, US Automaker made to order 16–28 wks
hyundai.com ↗ Seoul, KR Automaker made to order 16–28 wks
🇨🇳BYD
byd.com ↗
Shenzhen, CN EV & battery manufacturer made to order 16–28 wks

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