This document summarizes a summer internship project studying variations in wheel alignment parameters for commercial vehicles. It provides background on wheel alignment, describes the key alignment parameters like toe and thrust angle, and outlines the alignment procedure for Ashok Leyland Boss vehicles. Data is presented on measured toe-in and thrust angle values for a number of vehicles which show variations. Potential sources of this variation are discussed, including issues with sensors, fixtures, and inconsistencies during the alignment process.

1. SUMMER INTERNSHIP
PROJECT …

2. PROJECT TITLE
FROM: 1 JUNE 2014 TO 31 JULY 2014
DURATION: 31 DAYS
Study and analysis of variation in wheel
alignment parameters and identification
of sources of variation.

3. ASHOK LEYLAND…
TATA MOTORS
55%
ASHOK LEYLAND
25%
VOLVO EICHER
12%
OTHERS
8%
M-HCV Market share 2014
TATA MOTORS ASHOK LEYLAND VOLVO EICHER OTHERS
MAHINDRA AND
MAHINDRA
34%
TATA MOTORS
6%
ASHOK LEYLAND
5%
OTHERS
55%
SCV(2-3 T) MARKET SHARE 2014
MAHINDRA AND MAHINDRA TATA MOTORS ASHOK LEYLAND OTHERS

4. SPECIFICATION OF BOSS…
• GVW : 9.6 TONS
• Power : 120 hp
• Rear axle ratio : 4.56:1
• Axle load : 1. front :- 3100 kg. 2. rear: 6500kg
• Rim dia.: 16"
• Thrust angle range : -9 to +9 min.
• Toe in range : 0 to 2 mm.
• wheel base : 3500mm , 4500mm.
912
• GVW : 11.9TONS
• Power : 120 hp
• Rear axle ratio : 5.71:1
• Axle load : 1. front :- 4700 kg. 2. rear: 8200kg
• Rim dia.: 20"
• Thrust angle range : -9 to +9 min.
• Toe in range : 0 to 2 mm.
• wheel base : 3900mm , 4500mm,4900mm.
1112
• GVW : 12.9TONS
• Power : 120 hp
• Rear axle ratio : 5.71:1
• Axle load : 1. front :- 4700 kg. 2. rear: 9200kg
• Rim dia.: 20"
• Thrust angle range : -9 to +9 min.
• Toe in range : 0 to 2 mm.
• wheel base : 3900mm , 4500mm,4900mm.
1212

5. LAYOUT OF PLANT
W
GATE
FSM SHOP
AXLE SHOP
CWP AND
TIMING
GEAR SHOP
PAINT
SHOP
WELD SHOP
CPPS SHOP
SALES
YARD
ROUGH
MACHININ
G
GATE
CHASIS SHOP
VTS SHOP
FULLY BUILT
SOLUTION
power train
(engine and gear box manufacturing)
in / out IN for raw
material
DANA
CAB trim

6. SHOPS RELATED TO PROJECT
AXLE
SHOP
CHASSIS
SHOP
VTS
SHOP/PDI
SHOP

7. AXLE SHOP …
HERE AFTER TRACK ROAD FITTMENT THERE ARE TWO
SETTING OCCURS
1. SAP
2. TOE IN SETTING
IN ORDER TO CHECK END PLAY OF HUB
WE PERFORM END PLAY SETTING HERE
BY USING A DIAL GAUGE

8. CHASSIS SHOP…
DRESSING AREA
CHASSIS LINE 1
CHASSIS LINE 2
DRAG LINK
FITTMENT
CAB
DROP
MANUAL
MAXCUT
HYDRAULIC
MAXCUT
OFF
TRACK

9. WHEEL ALIGNMENT
INTRODUCTION :
• a wheel alignment consists of adjusting the angles of the wheels so that they are perpendicular to the ground and parallel
to each other.
• We perform wheel alignment of Boss, 3116, 3118but not of other vehicle because maximum speed of boss is around 90
km/h so its tendency of tire wear is more in its case.
The symptoms of a vehicle that is out of alignment are:
• Uneven or rapid tire wear
• Pulling or drifting away from a straight line
• Wandering on a straight level road
• Spokes of the steering wheel off to one side while driving on a straight and level road.

10. WHEEL ALIGNMENT PARAMETERS…
• Toe
• Thrust angle
• Camber
• Caster
• King pin
• Inclined angle
• Set back
• Toe out on turns
• Riding height
• King pin angle

12. WHEEL ALIGNMENT PROCEDURE FOLLOWED (BOSS)
• START computer and open Dynamic T Aligner in which we
already inserts standard value range of all the wheel aligner
parameters at the time of its instalment.
• It will ask us for various detail after pressing F4 which are
Number, company, customer, registration no., VIN, Km.
• After entering above details enter F4 again and we receive
the command
“Mount the sensor head”.
• We mount all the 4 clamp and then all the sensors on the
wheel rim, Enter F4 again.
• With the help of jack lift the BOSS from front axle check the
wheels for run out by simply rotate L.H and R.H wheel one
by one through 180 deg and after few seconds 180 deg
again in clockwise direction if there is run out goes out of
range then it will not proceed further and if it is within range
then same process should be done for rear wheel.

13. Procedure cont…
• If run out is ok then jack is removed click F4, and we get comment on
screen “steering a head and level head” which means turns the steering
on extreme left end and extreme right end then center the steering with
the help of steering lock and adjust the level of sensors.
• It will give the value and type of thrust angle, and if it is out of the given
range of -9 to +9 min then we need to adjust it by loosing U-bolts and
force it either in clockwise or anticlockwise according to the type of
thrust angle by using a iron lever requires lot of labor within the range.
• After setting it within the range then it will show other parameters value
like caster, Camber, king-pin angle, toe values etc.
• If toe in is lies within the range 0 – 1 mm then click F4 and get the
complete sheet of vehicle which involve every parameters. Otherwise
loose the nut of track rod and rotate it and adjust the toe in within range
and then tightening the bolts and then click on F4 button.
_ _
20’

14. PARAMETERS RELATED TO TOE IN
(DIAGNOSE VALUE )
Mean -0.95455
Standard Error 0.253196
Median -1.1
Mode -0.9
Standard Deviation 2.056972
Sample Variance 4.231133
Kurtosis 1.015269
Skewness 0.86039
Range 10
Minimum -4.8
Maximum 5.2
Sum -63
Count 66
0.40.5
1.5
5.2
-2-1.8
-2.1
-1.3
-0.1-0.1-0.2
0.4
1.2
-0.9
-0.6
-1.3
2.3
-0.6-0.8
-3.8
-2.7
-2.3
0.9
5.2
-2.8
-2.4
-1
-3.5
-4.8
-2.6
2.3
-2.6
-1.9
-0.4
-3.3
-0.9-0.8
-1.5
-3.3-3.4
0.3
-1.6
-2.8
-3.2
-0.9
2.8
-0.9
0
-2.1-2.3-2.1
-3.9
-2
-1.4
1.7
-1.2
-0.3
-2.3
3
-4
-2
-3.1
0.6
1.4
0.1
-0.9
-6
-5
-4
-3
-2
-1
0
1
2
3
4
5
6
0 10 20 30 40 50 60 70
TOTALTOEINVALUE
DIAGNOSE
NUMBER OF VEHICLE
VARIATION OF TOE IN VALUE
2 0
6
3
8 6
12
5 6 6
13
4
25
5 3
17
12
8
1
5 4
-4
9 11
-3
31
8
22
8
4
12
-4
1314
7
11
2
22
7 9
27
11
19
-11
-2
34
-21
1011
29
1819
7
17
3836
19
5
22
-13
13
2022
5
1719
-30
-20
-10
0
10
20
30
40
50
0 10 20 30 40 50 60 70
THRUSTANGLEVALUE
(DIAGNOSE)
NUMBER OF VEHICLE
VARIATION IN THRUST ANGLE
PARAMETERS
RELATED TO THRUST
ANGLE
DIGNOSE VALUE
Mean 10.62121
Standard Error 1.364
Median 9
Mode 5
Standard Deviation 11.08119
Sample Variance 122.7928
Kurtosis 0.787173
Skewness 0.113059
Range 59
Minimum -21
Maximum 38
Sum 701
Count 66

15. JULY
-9
-8
-7
-6
-5
-4
-3
-2
-1
0
1
2
3
4
5
0 10 20 30 40 50 60 70
TOEINDIGNOSEDVALUE
NUMBER OF VEHICLES
VARIATION OF TOE IN VALUE
-30
-20
-10
0
10
20
30
40
50
0 10 20 30 40 50 60 70
THRUSTANGLEDIGNOSEDVALUE
NUMBER OF VEHICLES
VARIATION OF THRUST ANGLE VALUE
PARAMETERS
RELATED TO TOE IN
(DIAGNOSED VALUE)
Mean -1.58983
Standard Error 0.295947
Median -1.9
Mode -1
Standard Deviation 2.273209
Sample Variance 5.167481
Kurtosis 0.510866
Skewness -0.07202
Range 11.5
Minimum -7.7
Maximu
m 3.8
Sum -93.8
Count 59
PARAMETERS
RELATED TO THRUST
ANGLE
(DIAGNOSE VALUE)
Mean 4.898305
Standard Error 0.64222
Median 7
Mode 8
Standard Deviation 4.932982
Sample Variance 24.33431
Kurtosis 1.529044
Skewness -1.53892
Range 18
Minimum -9
Maximum 9
Sum 289
Count 59

17. Sources of variations are:
Toe in
• Straight Ahead Position (SAP)
• Tolerance stack-up
• Rim irregularity
• Machine Related Variables
1.Repeatibility
2. Accuracy
FRONT WHEEL RIM

18. Cont..
• Run out compensation is not there
• Toe in setting gauge
• SAP Gauge axis shift
• Defect in toe in setting bracket
• Hub run out
FRONT VIEW TOP VIEW SIDE VIEW
SAP GAUGE Axis Shift
TOE IN SETTING GAUGE

19. Cont…
For Thrust angle.
• SAP Setting
• Tolerance stack-up
• Rim irregularity
• Machine related variables
• Fixtures
• L.H and R.H hole shift
• Pin hole clearance
• Spring mounting in FSM
• U-Bolts

20. Thank you !!! iiii