Foton Series Light Bus. Service Manual — part 12

OPERATION AND MAINTENANCE MANUAL FOR FOTON VIEW SERIES LIGHT BUS

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Figure 10-2-6 Side Cover Component of Transmission

1-Shifting rocker arm; 2-Big taper; 3-Dust boot; 4-Shifting shaft; 5-Rocker arm of selector; 6-Limiting stopper; 7-Pressue and

torsion spring; 8-Small taper; 9-Oil seal of shifting shaft; 10-Flat washer; 11-Oil seal of selector shaft; 12-Shifting block of shifting

shaft; 13-Spring seat; 14-Return spring; 15-spring column pin; 16-Transmission cover; 17-spring column pin; 18-Shifting cover

gasket; 19-Selector shaft; 20-Spring washer; 21-1 type hexagon nut; 22-Spring washer; 23-1 type hexagon nut.

Figure 10-2-7

1-Clutch housing; 2-Front housing component; 3-Reverse switch assembly; 4-seal washer; 5-Thrust ring of input shaft bearing;

6-Front bearing thrust ring of countershaft; 7-Housing; 8-Hexagon magnetic screw plug; 9-Hexagon screw plug; 10-Intermiedate

connecting plate component; 11-Rear body subassembly; 12-Return spring of Shifting block of shifting shaft; 13-Shifting rocker arm;

14-Selector rocker arm; 15-Dust boot; 16-Shifting shaft; 17-Limiting stopper of pressure and torsion spring; 18-Selector shaft;

19-Cover panel; 20-Bolt with washer.

Chapter 10 Chassis Structure and Service

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Figure 10-2-8 Intermediate Connecting Plate Component of Transmission (control part)

1-Shifting fork for 1st and 2nd gears; 2-Shifting fork shaft of 1st and 2nd gears; 3-Shifting slider of 1st and 2nd gears; 4-Fork

for 3rd and 4th gears; 5-Shifting slider of 5th gear; 6-Shifting fork shaft of 5th gear; 7-Shifting fork for 5th gear; 8-Shifting rocker

arm bracket component; 9-Shifting fork shaft of 3rd and 4th gears.

Figure 10-2-9 Intermediate Connecting Plate Component of Transmission (operating part)

1, 2-Input shaft subassembly; 3-Intermiedate connecting plate; 4-Rear bearing thrust ring of output shaft; 5-Rear bearing cap of

output shaft; 6-Hexagonal screw; 7-Front shaft snap ring of countershaft; 8-Front bearing thrust ring of countershaft; 9-Front bearing

of countershaft; 10-Connecting gear of countershaft; 11-Steel ball; 12-Rear bearing of countershaft; 13-Rear bearing thrust ring of

countershaft; 14-Thrust washer of 5th gear; 15-Needle bearing of neutral 5th gear; 16-Gear component of neutral/5th gears;

17-Synchronizer inserts of 5th gear; 18-Synchronizer gear ring for 3rd, 4th and 5th gears; 19-Synchronizer sliding sleeve of 5th gear;

20-Synchronizer gear ring for 3rd, 4th and 5th gears; 21-Connecting gear of 5th gear; 22-Rear shaft snap ring of countershaft;

23-Reverse idler component; 24-Reverse idler shaft; 25-Platen of reverse idler shaft; 26-Hexagon bolt with washer.

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Figure 10-2-10 Input Shaft Subassembly of Transmission

1-Snap ring; 2-Thrust ring of input shaft bearing; 3-Input shaft bearing; 4-Input shaft component;

5-Needle bearing; 6-Synchronizer gear ring for 3rd, 4th and 5th gears.

Figure 10-2-11 Front Cover Component of Transmission

1-Front cover; 2-Front cover oil seal assembly

Chapter 10 Chassis Structure and Service

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Figure 10-2-12 Output Shaft Subassembly of Transmission

1-Gear hub shaft snap ring for 3rd and 4th gears; 2-Synchronizer spring piston ring for 3rd, 4th and 5th gears; 3-Synchronizer

gear hub for 3rd and 4th gears; 4-Synchronizer insert for 3rd and 4th gears; 5-Synchronizer sliding sleeve for 3rd and 4th gears;

6-Synchronizer gear ring for 3rd, 4th and 5th gears; 7-Gear component of 3rd gear; 8-Needle bearing of 3rd gear; 9-Steel ball 6.35;

10-Output shaft; 11-Needle bearing of 2nd gear; 12-Gear component of 2nd gear; 13-Synchronizer gear ring for 1st and 2nd gears;

14-Synchronizer circlip for 1st and 2nd gears; 15-Synchronizer insert of 1st and 2nd gears; 16-Synchronizer gear hub for 1st and 2nd

gears; 17-Synchronizer sliding sleeve for 1st and 2nd gears; 18-Gear component of 1st gear; 19-Needle bearing of 1st gear; 20-Gear

shaft bush of 1st gear; 21-Rear bearing of output shaft; 22-Rear bearing check ring of output shaft; 23-Gear of 5th gear; 24-Gear shaft

snap ring for 5th gear; 25-Driving gear snap ring of odometer; 26-Driving gear of odometer.

Figure 10-2-13 Rear Body Assembly of Transmission

1-Oil drain channel; 2-Oil drain channel; 3-Rear body; 4-Rear body oil seal subassembly; 5-Rear body dust boot.

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Figure 10-2-14 Transmission Odometer Driven Gear Assembly

1-Oil seal; 2-O-ring; 3-Driven gear bracket of odometer; 4-Driven gear circlip of odometer; 5-Driven gear of odometer.

Figure 10-2-15 Shifting Control Device-1

Chapter 10 Chassis Structure and Service

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Figure 10-2-16 Shifting Control Device-2

Figure 10-2-17 Shifting Control Device-3

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Figure 10-2-18 Shifting Control Device-4

1.shift handle assbly 2.shift lever assbly 3.bolt M8*55 4.washer M-ZnD 5.nut M8-ZnD 6.shift shaft nylon nut 7.shift lever

8.shife lever assbly 9.return spring 10.shift shaft 11.shift spring upper bracket 12.washer M-AnD 13.nut M8-ZnD 14.bolt M8*100

15.bracket retaining boot 16.bracket retaining boot shaft 17.bolt 18.shift lever knob 19. vertical shift selector lever with hood assbly

20.vertical shift lever w.hood assbly 21.vertical selector rod w. hood assbly 22.hood retaining plate 23.vertical rod dust hood 24.nut

M8-ZnD 25.lower ball pin w.hood assbly 26.bolt 27.nut 28. I-shaft assbly 29.I-shaft right bracket assbly 30. shaft boot (A)

31.thrust ring16 32.I,II-shaft ball bush 33. shift right shaft sleeve assbly 34.shaft pin 35.shaft dust boot (B) 36. shaft sleeve 37.

I-shaft 38. I-shaft sleeve assbly 39. shift left shaft sleeve assbly 40. I-shaft left bracket assbly 41. bolt 42.shaft pin B8*26

43. shift drop arm boot 44. shift drop arm shaft sleeve 45. circlip 46.shift pull rod assbly 47. pin B8*18 48. retaining spring

49. selector long pull rod assbly 50. II-shaft assbly 51. II-shaft right braket retaining bush 52. II-shaft right bracket retaining

rubber boot 53. II-shaft right bracket 54. I,II-shaft ball bush 55. II-shaft dust boot 56. II-shaft right shift arm shaft sleeve assbly

57. shaft sleeve 58. II-shaft sleeve assbly 59. shaft dust boot(B) 60. II-shaft left shift arm assbly 61.thrust ring16 62. II-shaft

left bracket assbly 63. shaft dust boot (A) 64. shaft pin 65. bolt 66. bolt 67. nut M8 68. selector short pull rod w.boot

assbly 69.nut M8 70. washer 8-ZnD 71. short pull rod pin shaft 72.selector short pull rod assbly 73. flat washer 74.

selector drop arm rubber boot 75. selector drop arm shaft sleeve 76. shift short pull rod w. boot assbly 77. LH ball pin assbly

78. nut 79. shift short pull rod 80. nut M8 81. lower ball pin assbly 82. controls housing 83. pressure plate 84. shift lever

gurad hood 85. tap screw ST4.8*16-C-H 86. screw hole 87. washer 5-ZnD 88. tap screw ST5.5*16-C-H 89 (-) 90.

screw sets M8*16 91. clamp 92. shift operating cable assbly 93. shift operating handle assbly 94. screw sets M8*25 95.

screw sets M5*12 96. spring washer 97. nut M8 98. locating clip assbly 99. large washer 100. bolt M8*20 101. locating

clip II 102. flat washer 103. cotter pin

Chapter 10 Chassis Structure and Service

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Transmission drive mechanism usually adopts mesh bevel gear / lock ring inertia sychronizer construction. In

this mechanism, power enters inputshaft via countershaft to outputshaft. Except at D gear, all other gears transmit

power through countershaft by 2 pairs of gears, R gear drives with 3 pairs of gears.

Lock ring inertia synchronizer (figure 7-5-2) consists of sleeve (8), lock ring(9), splined hub(7), insert(2) and

spring circlip(6). Sleeve (8) engages lock ring (5,9) by using spring circlip’s radial pressure, the pressure pushes

insert (2) to sleeve and land its center convex perfectly on sleeve’s inner groove. The engagement is done when

insert’s both ends are put into notch center of lock ring (5,9). All these are the results of friction forces between

lock-ring (5,9) and gear meshed cone face, and also by rotating inertia value difference between clutch driven

parts and transmission gears, the difference makes hub (7) synchronizing with gear to be meshed, so that sleeve (8)

can mesh smoothly without causing impact among gears during shifting.

Figure 10-2-19 Lock ring inertia synchronizer

1- inputshaft gear 2-insert 3-fork 4-outputshaft gear 5-lock ring 6-spring circlip

7-spline hub 8-sleeve 9-lock ring 10-ring groove 11-axial grooves (3) 12-notch

10.2.3 Check and Repair

1. Transmission Housing

Check transmission housing for crack. Housing sets and their sizes should be in line with these values and

requirements in table 10-2-1. Bearing outer radius should match closely with bearing seat hole, otherwise operator

should galvanize bearing outer spherical suface to enlarge size, or even replace bearing.

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Table 10-2-1 Relevant service data -- Transmission Housing

Description

Specification (mm)

Planeness of housing top plane

Not more than 0.15

Diameter wear - input shaft bearing seat hole

≤0.08

Diameter wear - output shaft bearing seat hole

≤0.08

Diameter wear - countershaft bearing seat hole

≤0.05

Diameter wear - reverse gear shaft hole

≤0.05

Axis parallel —input/output shaft holes with countershaft hole

Not more than 0.08

Face run-out -- front end face with input/output shaft axis (within φ100)

Not more than 0.1

Face run-out -- rear end face with input/output shaft axis lines (within
φ100)

Not more than 0.1

2. Transmission Shaft

Check input/output /counter/ R gear shafts, repair if there is any bend on shaft journal or ecessive wear on

spline.

(1) Run-out on input/output /counter/ R gear shafts should be less that 0.2mm. Adjust or replace when

necessary.

(2) Replace shafts when spline wear width on input/output shafts exceeds 0.25, or fitting clearance with

groove is larger than 0.33mm..

(3) Galvanize to repair or replace when input/output/counter shaft bearing wear is less than 0.04mm.

(4) Replace input shaft when its gear tooth thinkness is less than 0.20mm or meshing clearance exceeds

0.40mm.

3. Synchronizer

Measure clearances between sychronizer insert and splined hub groove, insert and sychronizer lock ring

groove. Replace insert, lock ring or splined hub if wear exceeds tolerance. Concerning mating requirements on

sychronizer see table 10-2-2

.

.

Table 10-2-2 Mating Requirement for Synchronizer

Items

Standard assembly values

Service limit

Clearance--synchronizer insert and splined hub

groove

0.09~0.31

0.45~0.5

Clearance—insert and synchronizer lock ring

groove

4.24~4.58

5.0~5.2

Meshing area--synchronizer bevel ring inner face

and gear outer face

≥70%

≤60%

4. Transmission Cover and Shifting Mechanism

(1) Check transmission cover for crack. Cover’s inner surface planeness should be less than 0.15, otherwise

repair.

(2) Check these parts for wear, distortion or damage: selector fork, fork shaft, self-lock ball, locating spring,

interlock pin /hole, ball groove. Repair or replace parts when: a. wear exceeds 0.4mm on selector fork, fork shaft,

ball and interlock pin; b. groove excessive wear or wear depth exceeds 0.7mm; c. fork shaft bends, and its center

runout exceeds 0.1mm; d. locating spring is weak or broken.

Chapter 10 Chassis Structure and Service

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Figure 10-2-20 Check Shifting Fork for Bending and Figure 10-2-21 Check Shifting Fork for Wear

Distortion

10.2.4 Assembly and Adjustment

Before assembly, clean all transmission parts; apply sealant to sealing surfaces; soak all bearings with engine

oil; and apply a thin coat of engine oil to all matching surfaces. Adjust after assembly.

(1) Handling the shift level could shift to all gears freely. Otherwise make corresponding adjustment.

(2) Put assembled transmission onto test bench to perform load /non-load tests. Check operating status of

gears and check for noise and leakage. Directly install it onto the vehicle for testing after bench test. When

performing non-load running test (transmission input shaft Rpm is 1000rpm), the noise levels of gears (average)

generally should not exceed 90db.

(3) Operate shift level assembly, and observe shifting effect and if the working position of shift level

assembly is proper.

10.2.5 Typical Faults and Eliminations

1. Abnormal sound from transmission, see table 10-2-3.

Abnormal noise from transmission when engine is running at idle, noise is gone while clutch pedal is

depressed and re-occurs at releasing the pedal..

Table 10-2-3 Faults and eliminations—transmission abnormal noise

Causes

Solutions

1

Excessive wear and outer spherical larger gap to

housing -- inputshaft bearing

1

Replace bearing

2

Worn-out mesh gear

2

Replace gear

3

Worn-out output shaft bearing

3

Replace bearing

4

Gear fluid short or deteriorate

4

Add or replace fluid

5

Excessive worn selector fork/shaft

5

Replace selector fork/shaft

6

Excessive wear or damage on certain gear

6

Replace gear

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2. Meshing whine-transmission gears, see Table 10-2-4.

Whining becomes louder as vehicle speed goes up when transmission runs at a certain gear.

Table 10-2-4. Faults and eliminations—transmission gears whinning

Causes

Solutions

1

Excessive wear on certain gear sets, or poor run-in of

new gear

1

Replace gear or let proper run-in

2

Bearing has excessive play

2

Replace bearing

3

Gear fluid is short

3

Replenish fluid

3. Transmission gear jump-over, see table 10-2-5.

While vehicle is running, throttle openning change makes transmissions jumping over to N gear and

accelerating engine rpm.

Table 10-2-5 Faults and eliminations-- transmission gear jump-over

Causes

Solutions

1

Gear face is worn into cone shape; worn-out output

shaft splined face to create axial thrust

1

Replace the worn-out gear or output

shaft

2

Excessive inputshaft bearing play due to wear; worn

or damaged output shaft front bearing

2

Replace the bearing

3

Weak locating spring

3

Replace the locating spring

4

Excessive wear on shifting fork/shaft

4

Replace shifting fork shaft or fork

5

Poor gear meshing or distorted fork

5

Adjust the shifting controls or

repair the fork

6

Seriously deformed housing

6

Replace

4. Transmission overheating, see table 10-2-6.

After transmission has run for while, its housing temperature goes 40 ～ 50 ℃ higher than ambient

temperature, in worst case with “blue smoke” and burnt oil smell.

Table 10-2-6 Faults and eliminations—transmission overheating

Causes

Solutions

1

Transmission fluid is thin or short

1

Add or replace fluid

2

Too tight gear mesh or bearing grabbing

2

Adjust or replace parts

3

Bend outputshaft or bearing has excessive play

3

Replace outputshaft or bearing

5. Transmission leakage, see table 10-2-7.

There is fluid weeping or dropping at connecting spots on housing or on bolts after transmission has run for

certain mileage.

Chapter 10 Chassis Structure and Service

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Table 10-2-7 Faults and eliminations—transmission leakage

Causes

Solutions

1

Vent plug is clogged

1

Clear vent plug

2

Oil seal is damaged

2

Replace the oil seal

3

Loose oil filler plug, oil drain plug and bolt

3

Tighten corresponding parts. If necessary, apply

sealant.

4

Excessive transmission fluid

4

Remove excessive fluid

6. Shifting difficulty -- transmission, see table 10-2-8.

Cannot shift or shift with loud noise while vehicle is driving forward or backward.

Table 10-2-8 Faults and elminiations--shifting difficulty

Causes

Solutions

1

Too high fluid viscosity or too much fluid

1

Change or reduce fluid

2

Incomplete clutch release

2

Re-adjust the clutch

3

Stuck transmission shift/selector device

3

Remove stuck and impact at

corresponding parts

4

Difficult to shift to R gear

4

Check R gear rail or backup light

switch for stuck

10.3 Propeller Shaft

10.3.1 Main Technical Parameters of Propeller

Main Technical Parameters of Propeller

Sn

Items

Data

1

Type

Tubular and open type, needle bearing

universal joint

2

Universal joint

Cross (shaft diameter ×

tip-to-face distance)

(mm)

φ30×91

3

Tooth number of spline

shaft and sleeve fork

×modulus × pressure

angle

Internal spline of sleeve

fork of propeller

(Z × m× α)

21×1.27×30º

4

Flange yoke

4 φ10.2 holes with symmetrical rabbet

centers and 60 X 60 rectangle intersection

point distribution, convexity rabbet φ46

5

Propeller tube (outside diameter × wall thickness)

(mm)

φ68.9 X 2.3

6

Length

dimension

(mm)

Length of propeller shaft (bearing center

of front and rear universal joint flange

yoke)

1000

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Sn

Items

Data

7

Maximum working torque (N.m)

1600

8

The maximum cone angle at which the universal joint

will not produce movement interference

22º

9

Tightening torque for connecting bolt of propeller shaft

(N.m)

74±4

10

Maximum unbalance

30g.cm/3200r/min

11

Run out of propeller shaft (mm)

≤0．6

12

End clearance of cross bearing (mm)

0.05

10.3.2 Overview of Structure

Transmission output shaft axis intersects axis of rear axle drive gear, their corresponding position keeps

changing. Universal drive unit is employed to maintain power transmitting between these two. The unit is mainly

consisted of UJ, splined shaft, tube yoke, and propeller shaft, see Figure 10-3-1.

Figure 10-3-1 Propeller Shaft Assembly

1-Propeller shaft assembly; 2-Bolt; 3-Spring washer; 4-1 Nut; 5-Rear axle; 6- yoke

10.3.3 Check and Repair

After assembly has been dismantled, all parts should be washed with kerosene or diesel. Check them one by

one and perform necessary service and repair.

1. Exterior Check

(1) check cross shaft journal, spline shaft journal. If shallow dent or slight peeling is seen, one can use

grindstone to repair. Replace if necessary..

(2) Check flange yoke of universal joint for crack or other serious damage. Replace if necessary.

(3) Check propeller tube for distortion. The depth of depression on shaft tube should not exceed 2mm with

the area not more than 6cm

2

. It is not allowed to have more than 1 depression on tube.

(4) Check matching status between spline shaft and transmission. If excessive wear on spline is present,

replace the spline shaft.

2. Measurement and Check

(1) Propeller shaft angularity

Chapter 10 Chassis Structure and Service

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Support both ends of the propeller shaft tube on a V-stand after having removed paint rust at its both ends and

in the middle with sandcloth. Measure run-out at any points along the overall length of the shaft tube with a dial

indicator. If the reading exceeds 0.8mm, straighten the shaft tube on a press. Or replace it if correction does not

work.

(2) Cross shaft bearing radial clearance

Clamp cross shaft in vice, and put needle-bearing sleeve onto cross shaft journal. Push needle bearing up and

down. Use dial indicator to measure reading variations at highest point on bearing outer surface (figure 10-3-2). If

clearance reading exceeds rated value (standard: 0.05mm, limit: 0.15mm), cross shaft and bearing should be

replaced. If excessive diameter wear is present and exceeds the value specified (normal value φ30mm; service

limit φ29.85mm), replace the parts. If the wear extent on propeller shaft journal under oil seal exceeds 0.2mm,

repair or replace it.

Figure 10-3-2 Check Cross Shaft Bearing Clearance

10.3.4 Reassembly and Adjustment

1. Before remounting propeller assembly, one should clean parts thoroughly and apply general lithium grease

on bearing, oil seal and all fitting surfaces.

2. Check and adjustment

After reassembly, the propeller assembly should be tested and adjusted on a propeller dynamic balance tester.

Before the dynamic balance test, the run out at any point along the overall length of shaft tube should not exceed

0.8mm. The dynamic unbalance of propeller should not exceed 30gram.cm (at 3200rpm). After dynamic check,

weld counter weights to concerning spots on shaft tube both ends. Weld less than two weights at each end.

Perform again dynamic balance check after welding.

10.3.5 Typical Faults and Troubleshooting

1. Propeller shaft swings or vehicle body shivering during driving, see table 10-3-1.

While vehicle is driving, the driver can obviously feel strong oscillation transmitted from power train to

vehicle body, and the symptom varies at acceleration and coasting. The symptom diminished when vehicle stops

while engine runs at all rpm.

Table 10-3-1 Faults and eliminations- propeller shaft swings or vehicle body shivering during driving

Causes

Solutions

1

Distorted or bend propeller shaft

1

Repair or replace

2

Loose fittings or large dynamic unbalance

2

Repair, perform dynamic balance test

or replace.

3

Serious bearing wear

3

Replace

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2. Abnormal sound from propeller shaft, see table 10-3-2.

While vehicle is driving, driver can hear abnormal noise from propeller shaft, noise becomes more obvious at

shifting, and reduced or diminished when vehicle speed is steady.

Table 10-3-2 Faults and eliminations-abnormal sound from propeller shaft

Causes

Solutions

1

Serious wear on spline shaft and sleeve

1

Replace

2

Serious wear and grabbing on UJ bearing

2

Replace cross shaft or bearing

3

Distorted or bend propeller

3

Adjust or replace

3. Universal joint bearing heating, see Table 10-3-3.

After vehicle is driving for certain mileage, melted grease is found flowing out of center bracket bearing, and

parts become scalding.

Table 10-3-3 Faults and eliminations—UJ baring heating

Causes

Solutions

1

Grease short -- UJ bearing or center bracket

bearing

1

Apply grease

2

Bearing is skew

2

Adjust bracket till bearing is vertical

to propeller shaft

3

Oil seal is too tight

3

Running-in at low speed and apply

grease on lip

10.4 Rear Axle

10.4.1 Main Technical Parameters of Rear Axle

Main Technical Parameters of Rea Axle

Sn

Description

Data

1

Type of rear axle

Integral lute type or cannula type

Type

Cell grade retarder, hyperbola bevel gear

Main drive ratio

4．556

Number of tooth of drive bevel gear

9

Number of tooth of driven bevel gear

41

End

surface

circle

run-out

of

engagement flange (mm)

0.1

End surface radial circle run out of

engagement flange (mm)

0.1

2

Final drive

Engagement clearance between driven

gear and drive pinion (mm)

0.13~0.18

Type

Symmetrical bevel gear type

3

Differential

Engagement clearance of gears (mm)

0.05~0.20

Chapter 10 Chassis Structure and Service

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Sn

Description

Data

Type

Semi-suspension type

Diameter (mm)

φ32

Maximum radial circle run out (mm)

2

4

Half shaft

Maximum end surface circle run-out of

flange (mm)

0.2

Type

Stamping axle housing

Wheel span (mm)

1440

5

Axle

housing

Maximum diameter of rear axle

housing (mm)

φ272

6

Input torque (N.m)

860

7

Maximum allowable axle loading (kg)

2275/2665

8

Lubricant

GL-5, 80W/90 heavy duty gear oil

9

Lubricant volume(L)

1．6

10

Nut torque of hanger pin (N.m)

147±5

11

Torque of U-bolt (N.m)

123±5

10.4.2 Structure Overview

Rear axle consists of final drive, differential, halfshaft, wheel hub, wheel and axle case.

Final drive is used to reduce rotating speed and increase rotating torque, and change rotating direction for

longitudinal engine. In final drive, gears with fewer teeth drive these with more teeth, speed reduction thus is

obtained. Conical helix gear, if used, can change rotation direction. Final drive is set to a location before power is

distributed to drive wheels, which reduces torque that is transmitted by parts such as transmission and propeller

shaft, and the size and mass of these parts are also minimized.

Differential is a speed variation driving mechanism. Plantearyary gears’ rotation and revolution drive LH and

RH half shaft to rotate at different speeds, that ensures power transmission of each drive wheel at varied moving

conditions to avoid wheel skip. Differential transmits power to half shaft, wheel hub and wheel by means of half

shaft gears

Internal end of halfshaft is connected with halfshaft gear through a spline, and its external end is supported in

the flange of axle housing through bearings and connected with hubs. External end of halfshaft shaft is subjected

to a bending torque formed by acting forces from internal bearing in the axle housing and ground. This type of

support can only avoid bending torque to internal end of halfshaft, while the external end will bear all bending

torque; therefore, it is called “semi-suspension” support.

Generally, driving axle housing is made up of final drive housing and halfshaft sleeve, in which the final

drive, differential and halfshaft are installed. Exterior of driving axle housing is connected with body through

suspension, brake base plates will be installed on its both ends. The driving axle housing takes various acting

forces and torques transferred from suspension and wheels.

BJ6486, BJ6516 series light bus is equipped with non-divided driving axle, single stage hypoid gear final

drive, bevel planteary gear differential, semi-suspension halfshaft, integral stamping and welding axle housing and

common rear wheel hub etc., see Figure 10-4-1, Figure 10-4-2 and Figure 10-4-3.