The document provides information about a training module on steering systems and propeller shafts for low floor buses. The module objectives are to identify parts, perform checks and maintenance, and troubleshoot steering systems and propeller shafts. It describes the components and functions of steering systems like rack and pinion, issues like steering adjustments and bleeding procedures. It also details the components, removal and installation of propeller shafts and common troubleshooting issues like vibration and premature wear.

1. Technician Level 2 (LOB Bus) – Module 4
Steering System & Propeller Shaft of Low Floor RE Bus

2. Introductions
Please introduce yourself loud and clear including your details for:
 Participant Name
 Dealership Name
 Location
 Experience in Tata Motors (In years & months)
 Hobbies &
 What Bonds you with TATA MOTORS
7/26/2022 TML 2

3. Program Objective
At the end of this module the participants will be able to:
 Identify the parts of Steering System
 Perform basic checks on the Steering System
 Perform preventive maintenance on Steering System
 Perform adjustments on the Steering System
 Perform inspection of components
 Identify the parts of the propeller shaft
 Removal and Refit procedure for Propeller Shaft
 Perform preventive maintenance of the propeller shaft
 Troubleshooting of propeller shaft
7/26/2022 TML 3

4. Program Agenda
 Introduction to Steering System
– Low floor Bus
– High Deck Bus - DIVO
– Operation and components
 Steering System Overview
– Adjustment Procedures
– Troubleshooting
– Inspection & Adjustment
– Bleeding procedure
 Propeller Shaft
– Introduction
– Construction of Prop Shaft
– Removal and Install procedure
– Troubleshooting
7/26/2022 TML 4

5. Low Floor Bus & Hi-Deck Bus (DIVO)
Introduction to Steering System
7/26/2022 TML 5

6. Purpose & Function of Steering System
 Control of front wheel (sometimes rear wheel) direction.
 Transmit road feel (slight steering wheel pull caused by the road surface) to the drivers hand.
 Maintain correct amount of effort needed to turn the wheels.
 Absorb most of the shock going to the steering wheel as the tire hits holes and bumps in the
road.
 Allow for suspension action.
7/26/2022 TML 6

7. Basic Layout of Steering Systems
7/26/2022 TML 7

8. Types of Steering System
7/26/2022 TML 8

9. Types of Steering System
7/26/2022 TML 9
Steering System
Mechanical Power
Rack & Pinion Hydraulic
Worm & Roller
Electrical / Electro-
hydraulic
Rack & Pinion Worm & Roller
Recirculating
Ball & Nut
Hydrostatic
(Gerotor)
Column Driven
EPS
Pinion Driven
EPS
Rack & Pinion
Rack Driven EPS
Recirculating Ball & Nut

10. Power Steering
Need For Power Steering
 Power Steering is needed to achieve greatest possible road safety under:
– Increasing traffic density
– High axle loads
– Poor road conditions
Benefits of Power Steering
 Effortless Steering
 Quick and Precise response
 Absorbs road shocks
 Greater safety and controllability under critical situations
7/26/2022 TML 10

11. Hydraulic Power Steering
7/26/2022 TML 11

12. Steering Gear Box used in Low Floor Buses
 Integral hydraulic ball & nut type power steering gear box (TYPE 8043)
7/26/2022 TML 12

13. Technical Specifications
7/26/2022 TML 13
Particular Description
Model ZF 8043
Type Integral hydraulic ball & nut type
Steering Ratio 20.2:1
Steering Oil Capacity 7 Liters
Oil Grade ATF-Type A
Vehicle Models with this Gear Box LPO 1623 CNG RE LE
LPO 1624 Diesel RE LE
LPO 1625 CNG RE LE
LPO 1925 Hybrid
A Company's symbol
B Country of origin: Made in Germany
C ZFLS number
E OE number
F Production number
G Date of production: MM / YY
H Pressure

14. Exploded View of ZF 8043
7/26/2022 TML 14

15. Steering Gear Box used in Hi-Deck Bus (DIVO)
 Integral hydraulic ball & nut type power steering gear box (TYPE 8098).
7/26/2022 TML 15

16. Technical Specifications
7/26/2022 TML 16
Particular Description
Model ZF – Servocom 8098
Type Integral hydraulic ball & nut type
Steering Ratio Variable Steering Ratio
Steering Oil Capacity 7 Liters
Oil Grade ATF-Type A
Vehicle Models with this Gear Box LPO 1628 Hi-Deck “DIVO”
A Company's symbol
B Country of origin: Made in Germany
C ZFLS number
E OE number
F Production number
G Date of production: MM / YY
H Pressure

17. Exploded View of ZF 8098
7/26/2022 TML 17

18. Bevel Gear
 Steering wheel motion is transferred to steering gear box via bevel gear.
 Motion is converted to 90 degrees at bevel gear.
 Max. torque on bevel gear box input shaft is 10 mkg.
 Bevel Gear box has life time lubrication.
7/26/2022 TML 18

19. Exploded View of Bevel Gear
7/26/2022 TML 19

20. Power Steering Oil Reservoir
7/26/2022 TML 20

21. Steering System Overview
7/26/2022 TML 21

22. Special Tools
 Servo Tester Gauge
 Tongue for piston assembly
 Assembly vice for steering gear
 Torque measuring device
7/26/2022 TML 22

23.  Please follow the instructions of the trainer
Practical Exercise
7/26/2022 TML 23
Adjustment and testing
of steering gear
Duration – 60 mins

24.  Please follow the instructions of the trainer
Practical Exercise
7/26/2022 TML 24
Troubleshooting
Duration – 120 mins

25.  Please follow the instructions of the trainer
Practical Exercise
7/26/2022 TML 25
Bleeding & Oil filling
procedure
Duration – 60 mins

26. Propeller Shaft
7/26/2022 TML 26

27. Function of Propeller Shaft
 The basic function of a propeller shaft is to transmit power from one point to another in a
smooth and continuous action.
 The propeller shaft must operate through constantly changing relative angles between the
transmission and axle.
 It must also be capable of changing length while transmitting torque.
 This change in angle and length is accomplished by using universal joints & slip joints
respectively.
The propeller shaft geometry in side view
(Vertical Offset)
The propeller shaft geometry in top view
(Horizontal Offset)
7/26/2022 TML 27

28. Components of Propeller Shaft
7/26/2022 TML 28
End Yoke
U J Cross

29. Removal & Re-fitment of Propeller Shaft on Vehicle
7/26/2022 TML 29

30. Removal Procedure
 Position support ropes to make sure that the driveshaft will be properly supported.
 Mark the slip yoke assembly and tube shaft with a marking stick or paint to ensure proper
alignment when reassembled.
 This is known as keeping the driveshaft yoke in phase.
7/26/2022 TML 30

31. Re-fitment Procedure
 Place the driveshaft in support ropes & make sure the driveshaft is in its original orientation.
 In case of companion flange design at the ends – Working from the front end, position the
flange yoke face into the companion flange, aligning bolt holes & phasing marks.
 Install new bolts, washers & nuts (if required).
 In case of Half Round End Yoke design at the ends – Working from the front end, position the
UJ Kit assembly properly on the Half Round End Yoke assembly so that the bearing cups are
well placed between the collars on the Half Round End Yoke.
 Install new strap & strap bolts.
7/26/2022 TML 31

32. Re-fitment Procedure..
 Be sure the second support rope is in place, it may be necessary to collapse slip member
assembly to allow clearance to install the drive shaft into the rear companion flange/Half
Round End Yoke.
 Install new bolts, washers & nuts (if required) for companion flange design and strap bolts in
case of half round end yoke design.
 Completely re-lubricate all Universal Joints & the Slip joint assembly.
 Remove all support ropes.
Caution: Half Round self locking retaining bolts should not be reused.
7/26/2022 TML 32

33. Tightening Torque
7/26/2022 TML 33

34. Tightening Torque
7/26/2022 TML 34

35. Troubleshooting
7/26/2022 TML 35

36. Vibration
 Low gear shudder.
 At certain speeds under full drive or full
coast.
 Under light loaded conditions.
Causes
 Secondary couple load reaction at shaft
support bearing.
 Improper phasing.
 Incompatible driveshaft.
 Driveshaft weight not compatible with
engine transmission mounting.
 Driveshaft too long for speed.
 Loose outside diameter fit on slip spline.
 Excessively loose u-joint for speed.
 Driveshaft out of balance, not straight.
 Unequal u-joint angles.
 U-joints angle too large for continuous
running.
 Worn u-joint.
 Inadequate torque on bearing plate cap
screws.
 Torsional and/or internal excitation.
7/26/2022 TML 36

37. Vibration
Corrections
 Reduce u-joint continuous running angle.
 Replace u-joint.
 Install two piece driveshaft with shaft support bearing.
 Use larger diameter tube.
 Shim drivetrain components to equalize u-joint angles.
 Straighten and balance shaft.
 Check with transmission or axle manufacturer replace shaft bearing.
 Inspect u-joint flex effort for looseness - torque to specification.
 Check driveshaft for correct yoke phasing.
7/26/2022 TML 37

38. Premature Wear
 Low mileage u-joint wear.
 Repeat u-joint wear.
 End galling of cross trunnion and bearing assembly.
 Needle rollers brinelled into bearing cup and cross trunnion.
 Broken cross and bearing assemblies.
7/26/2022 TML 38

39. Premature Wear
Causes
 End yoke cross hole misalignment.
 Excessive angularity.
 Improper lubrication.
 Excessive u-bolt torque on retaining nuts.
 Excessive continuous running load.
 Continuous operation at high angle/high speed.
 Contamination and abrasion.
 Worn or damaged seals.
 Excessive torque load (shock loading) for u-joint and driveshaft size.
7/26/2022 TML 39

40. Premature Wear
Corrections
 Check for end yoke cross hole misalignment, replace end yoke if misaligned.
 Check u-joint operating angles with a spirit level protractor or Spicer Anglemaste II Electronic
Driveline Inclinometer, reduce excessive u-joint operating angles. Lubricate according to
Spicer specifications.
 Replace u-joint kit.
 Reduce u-joint continuous running angle.
 Replace with higher capacity u-joint and driveshaft.
 Check u-joint flex effort - replace joint or yoke if necessary.
 Clean and re-lubricate u-joint.
 Realign to proper running angle - minimum ½ degree.
 Torque bearing retention method to specification.
7/26/2022 TML 40

41. Slip Spline Wear / Tube Broken
 Seizure
 Galling
 Outside diameter wear at extremities and at
180 degrees.
 Spline shaft or tube broken in torsion.
Causes
 Improper lubrication.
 Worn or damaged part.
 Tube size inadequate.
 Excessive torque load for u-joints and
driveshaft size.
 Male spline head engagement length too
short for application.
 Excessive loose outside diameter fit.
 Slip member working in extreme extended
or fully collapsed position.
 Contamination.
7/26/2022 TML 41

42. Slip Spline Wear / Tube Broken
Corrections
 Lubricate slip spline according to Spicer specifications.
 Replace with higher capacity u-joint and driveshaft.
 Check u-joint flex effort - replace joint or yoke if necessary.
 Clean and re-lubricate according to Spicer specification.
 Replace spline - check design for application.
 Use Spicer GlidecoteTM slip spline.
 Increase driveshaft assembly length to position slip spline head towards u-joint.
 Check for male slip member with longer spline.
 Use larger diameter tube.
7/26/2022 TML 42

43. Shaft Support Bearing And / Or Tube
 Shaft support bearing wear or fracture.
 Shaft support rubber insulator wear or fracture.
 Tube circle weld fracture.
Causes
 Balance weight located in apex of weld yoke lug area.
 Balance weight too close to circle weld.
 Improper circle weld.
 Bending fatigue due to secondary couple loads.
 Driveshaft too long for operating speeds.
 Worn or damaged parts.
 Excessive torque load (shock loading) for u-joint and driveshaft size.
 Improper lubrication of bearings.
 Shaft support bearing misaligned.
 Interferes with slinger.
7/26/2022 TML 43

44. Shaft Support Bearing And / Or Tube
Corrections
 Reduce u-joint continuous running angle.
 Replace with higher capacity u-joint and driveshaft.
 Install two piece driveshaft with shaft support bearing.
 Use larger diameter tube.
 Normal bearing wear - replace.
 Realign mounting bracket to frame cross member to eliminate interference with slinger.
7/26/2022 TML 44

45. Yoke Fracture
 Yoke broken in hub.
 Yoke broken at ear tip.
Causes
 Mating yoke lug interference at full jounce
and rebound.
 Excessive torque load for u-joint and
driveshaft size.
 Improper shaft length and slip.
 Bending fatigue due to secondary couple
loads.
Corrections
 Reduce u-joint continuous running angles.
 Replace yoke-check design for application.
 Use wide angle yokes.
 Check installed lengths and adjust driveshaft
length to provide proper slip conditions.
7/26/2022 TML 45

46. All The Best!!!
7/26/2022 TML 46