Chrysler RAM TRUCK 2500 1994 Service Manual page 22

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INTRODUCTION 17
F A S T E N E R T O R Q U E INFORMATION AND METRIC C O N V E R S I O N
SPECIFICATION NOTATIONS
WARNING: T H E U S E O F I N C O R R E C T ATTACHING
HARDWARE CAN R E S U L T IN COMPONENT DAM­
A G E AND/OR P E R S O N A L INJURY.
I t is important to retain the original attaching
hardware for assembly of the components. I f the at­
taching hardware is not reusable, hardware with
equivalent specifications must be used.
METRIC AND ENGLISH/SAE CONVERSION
The following chart will assist in converting metric
units to equivalent English and SAE units, or vise
versa.
TORQUE SPECIFICATIONS
T O R Q U E CHARTS
A torque chart for fasteners is provided at the end
of each group (of service information). Refer to the
Standard Torque Specifications chart to determine
torque values not listed in the group (Figs. 1 and 2).
It is important to be aware that the torque values
listed i n the chart are based on clean and dry bolt
threads. Reduce the torque value by 10 percent when
the bolt threads are lubricated and by 20 percent i f
new.
B O L T T H R E A D AND GRADE/CLASS
IDENTIFICATION
THREAD IDENTIFICATION
SAE and metric bolt/nut threads are not the same.
The difference is described i n the Thread Notation
chart.
GRADE/CLASS IDENTIFICATION
The SAE bolt strength grades range from grade 2
to grade 8. The higher the grade number, the greater
the bolt strength. Identification is determined by the
line marks on the top of each bolt head (Fig. 1). The
actual bolt strength grade corresponds to the number
of line marks plus 2.
• A grade 2 bolt has no line marks on top of the bolt
head
• A grade 5 bolt has 3 line marks on top of the bolt
head
CONWERSION FORMULAS AND EQUIWALENT WALUES
M u l t i p l y
in-lbs
ft-lbs
B y
x 0.11298
x 1.3558
To G e t
= Newton-Meters (Nhm)
= Newton-Meters (N*m)
Multiply
N f n
N*m
B y
x 8.851
x 0.7376
T o G o t
= In-lbs
- ft-lbs
Inches H g (60°F)
psi
x 3.377
x 6.895
« Kilopascals (kPaj
= Kilopascals (kPa)
kPa
kPa
x 0.2961
x 0.145
= Inches H g
- psi
Inches
Feet
Yards
Miles
x 25.4
x 0.3048
x 0.9144
x 1.6093
Millimeters (mm)
= Meters (M)
» Meters (M)
= Kilometers (Km)
mm
M
M
Km
x 0.03937
x 3.281
x 1.0936
x 0.6214
= Inches
- Feet
- Yards
- M i l e s
m p h
Feet/Sec.
Kilometers/Hr.
m p h
x 1.6093
x 0.3048
x 0.27778
x 0.4470
= Kilometers/Hr. (Km/h)
« Meters/Sec. (M/S)
= Meters/Sec. (M/S)
« Meters/Sec. (M/S)
K m / h
M / S
M / S
M / S
x 0.6214
x 3.281
x 3.600
x 2.237
= m p h
- Feet/Sec.
= Kilometers/Hr.
« rnph
C O M M O N METRIC E Q U I V A L E N T S
1 Inch « 25 Millimeters 1 Cubic Inch « 16 Cubic Centimeters
1 Foot = 0.3 M e t e r 1 Cubic Foot - 0.03 Cubic Meter
1 Yard « 0.9 Meter 1 Cubic Yard = 0.8 Cubic Meter
1 M i l e = 1 . 6 Kilometers
J91IN-1