Vehicle Maintenance-100% reliable maintenance methods
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Use and Maintenance of Principal Assembly

How to Perform Vehicle Maintenance and Appendixes

Maintenance category

According to different uses and service conditions of the vehicle, as well as the expected annual traveling mileage, the vehicle maintenance system is divided into three classes:

  • Class I: The service condition is poor (cold or hot climate, high dust content, short-distance transportation, off-road use) or the annual vehicle traveling mileage is less than 20,000km.
  • Class II: Short, medium-distance transportation, the annual vehicle traveling mileage is less than 60,000km.
  • Class III: Long-distance transportation, the annual vehicle traveling mileage is more than 60,000km.

Interval mileage of routine inspection and maintenance

Table of interval mileage of routine vehicle inspection and maintenance under the various serious conditions (as shown in Table 1) Unit: 1,000km

Class II
mainte nance

Routi ne



Class I mainte nance

Routi ne 



Class III
mainte nance

Routi ne



Class I mainte nance

Routi ne



Class II
mainte nance

Routi ne



Class I mainte nance

Routi ne



Class IV
mainte nance

Daily Vehicle Maintenance Items

  1. Check the parking brake and foot brake.
  2. Check the lighting and the service conditions (engine oil pressure, air reservoir pressure, air filter maintenance indicator light, charging indicator light, etc.) of signal system and all kinds of indicator lights.
  3. Check the tractor tire pressure and condition.4 Check the engine oil, transmission hydraulic oil, cooling liquid and fuel level.
  4. Check the steering hydraulic oil level, temperature.
  5. Check the steering hydraulic oil temperature.
  6. Check whether the tractor and trailer connecting device is in normal condition.

Table of Vehicle Maintenance Items Of All Classes

EngineInitial inspectionRoutine inspectionClass I
Class II
Class III
Class IV
Replace the engine oil (at least once every year) ※ ※ ※ ※ ※
Replace the filtering element of oil filter ※ Every time replace the engine oil
Check and adjust the valve clearance※ ※ ※ ※※
Check the opening pressure of oil nozzle    ※
Clean the rough filter of fuel pump ※ ※ ※
Replace the filtering element of fuel filter※ ※ ※※※※
Check the cooling liquid volume and fill up ※ ※ ※ ※ ※ ※
Replace the cooling liquid Every 24 months
Fasten the cooling pipe clamp ※
Fasten the inlet pipe hose and flange connection ※ ※ ※ ※ ※
Check the air filter blocking alarm switch ※ ※ ※ ※
Clean the dust cup of air filter ※ ※ ※ ※ ※
Clean the main filtering element of air filter When the indicator light is on
Replace the main filtering element of air filter   When the main filtering element is damaged Replace the safety filtering element of air filter After cleaning the main filtering element for 5 times Check and fasten the V-belt ※ ※   ※ ※ ※ ※
Check the booster bearing clearance ※ ※
Check the fuel injection pump ※
Adjust the idling speed ※
Check the connection and fixation of intercooler inlet pipe ※ ※ ※ ※ ※ ※
Transmission Please refer to the transmission accompanied data for inspection and adjustment of  transmission part
Check the transmission hydraulic oil level ※ ※ ※
Replace the transmission lubricating oil (at least once every year) ※ ※ ※ ※
Check the connection and fixation of oil pipe from transmission to cooler ※ ※ ※ ※
Check the transmission oil thermometer operating condition ※ ※ ※ ※
Check the throttle sensor operating condition ※ ※ ※
Check the operating condition of the transmission fault indicator light ※ ※ ※ ※ ※
Transmission shaft 
Refasten the transmission shaft bolt Retighten the transmission shaft bolt when it initially travels 1,200km, and after that, retighten the transmission shaft bolt for every traveling of 3,000km.
Clean the ventilation device ※ ※ ※ ※
Check and adjust the hub bearing clearance       Carry on during the first Class-2 maintenance                                                                      Check and adjust the bearing clearance             Carry on during the first Class-2 maintenance                                                                       Replace the hub lubricating grease   ※ ※
Check the wiper action ※ ※ ※ ※ ※ ※
Check oil level of the cab flip oil pump ※ ※ ※
Check the lifting cylinder installation condition ※ ※ ※ ※ ※                                                                                                                                  Check the operating condition of hydraulic lock and damper ※  ※  ※                                                                                                              Check the service condition of backdoor lock ※  ※   ※
Check the condition of front flip points ※ ※ ※
ChassisInitial inspectionRoutine inspectionClass I
Class II
Class III
Class IV
Check the fixation of front axle damper ※ ※ ※ ※ ※
Check and adjust the clearance of the steel plate spring side baffle   ※  ※ ※                                                                                                        Fasten the front, rear steel plate spring U-shape bolt and bracket ※ ※ ※ ※                                                                                                        Check the tire pressure ※ ※
Check the fixation of traction gear ※   ※  ※  ※ ※                                                                                                                                                Check the fixation of wheel nut ※  ※ ※ ※ ※                                                                                                                                                          Check the fixation of battery, air reservoir         ※ ※ ※                                                                                                                                    Check the fixation of fuel tank  ※   ※ ※ ※                                                                                                                                                            Check the fixation of fender board   ※    ※  ※  ※
Brake system
Drain water from the air reservoir ※ ※ ※ ※ ※ ※
Check the pressure system tightness (barometer inspection) ※ ※ ※ ※  ※                                                                                                        Clean the filtering screen of pressure regulating valve of the dryer  ※ ※ ※                                                                                                  Check the thickness of brake friction disc, and adjust the brake clearance  ※ ※ ※                                                                                      Clean the wheel brake ※ ※
Check the easily abraded part of brake pipeline and hose ※ ※ ※ ※
Check the function of brake chamber ※ ※ ※ ※
Check the function of foot brake, hand brake and exhaust brake (carry on during test run) ※ ※ ※ ※ ※
ElectricalInitial inspectionRoutine inspectionClass I
Class II
Class III
Class IV
Check the operation condition of the electrical system (signal light, headlight, width light, wiper, heating and ventilation device) of tractor and trailer ※ ※※※※※
Check the liquid level and proportion of battery electrolyte as well as the voltage of each battery cell ※※ ※ ※ ※
Check the fixation of battery terminal, and apply lubricating grease on the electrode ※ ※ ※ ※ ※
Check the correctness of electronic tachometer speed ※ ※ ※ ※ ※ ※
Check the correctness of speedometer speed ※ ※ ※ ※ ※ ※
Steering systemInitial inspectionRoutine inspectionClass I
Class II
Class III
Class IV
Check and adjust the positioning of front wheel ※
Check the oil level height of steering oil tank ※ ※ ※ ※ ※
Replace the oil filer of steering oil tank ※ ※
Check the connection of steering oil pipe ※
Check the fixation of steering oil pipe ※
Check the function of steering system ※ ※
Saddle lifting systemInitial inspectionRoutine inspectionClass I
Class II
Class III
Class IV
Check the leakage condition of hydraulic pipe connector     Once every day 
Check the leakage condition of hydraulic cylinder                Twice every week
Check or replace the gooseneck front supporting pad         Once every half a year 
Check the leakage condition of control unit bank                 Twice every week

Carry on the anti-rust state inspection to the cab for every 12 months, and if necessary, carry on the anti-rust supplementing treatment.

Assembly oil-changing interval mileage

CategoryEngineTransmissionRear axleSteering systemCab lifting systemRemarks
Initial inspectionThe initial inspection  is after the engine operating reaches 100h
Routine inspection    
Class I maintenance    
Class II maintenance
Class III maintenance
Class IV maintenance

Lubricating grease lubrication points

NoLubrication partPlac esUsagePeriodRemarks
1Engine water pump1120gOnce every 400h 
2Steering master pin2As neededOnce every 400h 
3Cab damper3As neededOnce every month 
4Cab hydraulic lock1As neededOnce every month 
5Cab flip shaft2As neededOnce every month 
6Front axle brake arm2As neededOnce every 400h 
7Front axle brake camshaft2As neededOnce every 400h 
8Drive axle brake camshaft2As neededOnce every 400h 
9Cab door hinge4As neededOnce every half a year 
10Front suspension pin shaft6As neededAt least once every month 
11Transmission shaft3As neededOnce every month 
12Front suspension damper2As neededAt least once every week 
13HubEach600gAt least once every year 
14Traction seat junction surface1As needed Contact surface fully applied
15Swing arm rotating point2As needed  
16Cast steel traction seat rotating shaft2As needed  
17Traction seat lifting cylinder4As needed  

1. Lubrication part, usage, period

h: Engine motorcycle calculated in hour / hour

Notes: After the vehicle cleaning, all lubrication points shall be refilled with lubricating grease.

2.Lubrication point distribution diagram

2.1 4×2 model lubrication point distribution diagram

Vehicle Maintenance 2

Braking schematic diagram

1. Barometer

2. Brake master valve

3. Air horn

4. Push button valve

5. Hand brake valve

6. Front axle brake chamber


7. Air compressor

8. Main intake pipe

9. Spiral pipe

10. Trailer connector

11. Fuel cut-off cylinder

12. Air reservoir

13. Traction seat unlocking cylinder

14. Dual-chamber brake

15. Hand brake relay valve

16. Air reservoir

17. Foot brake relay valve

18. Air reservoir

19. Four circuit protection valve

20. Dryer

21.Butterfly valve switch cylinder

22. Trailer brake valve

23. Shut-off valve

Steel plate spring specifications

ModelDrive typePositionSpecification (pieces × thickness × width) mmRemarks
Riveted frame4×2Front4×22×90 
Rear(9×18×100) +(6×16×100) 
Rear12×22×90Main spring of 4 pieces
Welded frame4×2Front9×13×90 
RearRigid suspension 
RearRigid suspension 
 Material50CrVAGenerally used for all models

Service data of commonly used vehicles

AssemblyOil productDesignationCapacity
Fuel tankDieselCondensation point in summer<0°CGB252 top-grade No. 0 light diesel230L
Condensation point in winter<-20°CGB252 top-grade – No. 20 light diesel
Cooling systemWD(T)615Cooling liquidHeavy-duty four-season lasting anti-freezing solution40L
MC(T)07-35℃ working solution, I type Q/ZZ21007(BASF G48-24-35℃)25-30L
TransmissionZF S6-120Heavy-duty vehicle gear oil85W/90 GL-511L
AllisonAllison transmission special oilTranSyndTM27L
ShuangteShuangte transmission special transmission fluidDexron IIIH28L
Steering systemMechanical steeringSteering fluidATFⅢ automatic steering fluid5L
Fully hydraulic steering46# anti-wear hydraulic oil20L
Saddle lifting systemHydraulic oil46# anti-wear hydraulic oil40L
Cab flip mechanismHydraulic oilNo. 10 aviation hydraulic oil0.4L
ClutchBrake fluidDOT3About 1L
Drive axleMain reducerHeavy-duty vehicle gear oil85W/140 GL-56.3L
Wheel reducerHeavy-duty vehicle gear oil85W/140 GL-52.4L (each side)
PR70 power take-offHeavy-duty vehicle gear oil85W/140 GL-51.5L

Table of tire pressure parameters

ModelSingle tire (KPa)Double tire (KPa)
11.00-20 (Level-18)910840
12.00-20 (Level-18)810740
12.00-24 (Level-18)810740
11.00R20 (Level-18)930
12.00R20 (Level-18)830
12.00R24 (Level-18)830
11R22.5 (Level-16)830
12R22.5 (Level-16)830
315/80R22.5 (Level-18)830
295/80R22.5 (Level-16)830
425/65R22.5 (Level-18)760

Table of wheel parameters

Rim typeTwo-piece typeTwo-piece typeTwo-piece typeOne-piece typeOne-piece typeOne-piece type
Tire specification11.00-20/

Main structure description

  1. Engine: Special engine of Sino Truck.
  2. Front axle: Fist-type I-shape special rigid front axle, drum brake.
  3. Rear axle: Steyr punching reinforced center, wheel rim two-stage reduction rear axle, total speed ratio of 10.77.
  4. Suspension: The front suspension of riveted frame model is a vertical steel plate spring belt drum-type damper, and the rear suspension is a primary, secondary steel plate spring suspension. The front suspension of welded frame model is a vertical steel plate spring belt drum-type damper, and the rear is a rigid suspension.
  5. Steering system: The welded frame model is mechanical steering, and the diameter of steering wheel is 420mm.
  6. Clutch: Single-piece dry type, hydraulic gas control type, 420, it is a periphery mounted spiral spring.
  7. Brake system: WABCO brake system, it adopts the Germany’s VOSS quick connector.
  8. Electrical equipment: Single-wire system, 24V, negative earth; 2×12V/165Ah battery, headlight, left, right front turning light, front fog light, width light, brake, light, back-up light, interior light, reversing light, combination instrument, transmission oil thermometer (automatic transmission accessory), transmission fault indicator light (automatic transmission accessory), reserved 24V wireless terminal equipment spare power cord (such as connection of the attached transformer, variable pressure of 12V), 24V power supply socket.
  9. Cab: The cab is a skeleton covering structure, and adopts the VDO electrical system of Sino Truck.
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