Dodge RAM TRUCK 1500 1995 Service Manual page 33

28 INTRODUCTION
B R
THREAD NOTATION—SAE
AND METRIC
I N CH
METRIC
5/16-18 M8 X 1.25
T H R E A D NUMBER T H R E A D DI S TANCE
MAJOR OF MAJOR BETWEEN
DI A METER THREADS DI A METER IN THREADS IN
IN I N CHES PER INCH MI L LI M ETERS
MILLIMETERS
PR606B
HAiE/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. The actual
bolt strength grade corresponds to the number of line
marks plus 2. The most commonly used metric bolt
strength classes are 9.8 and 12.9. The metric
strength class identification number is imprinted on
the head of the bolt. The higher the class number,
the greater the bolt strength. Some metric nuts are
imprinted with a single-digit strength class on the
nut face. Refer to the bolt identification and bolt
strength chart.
METRIC CONVERSION
Refer to the chart to convert torque values listed in
metric Newton-meters (N-m). Also, use the chart to
convert between millimeters (mm) and inches (in.)