
'Jeep'
UNIVERSAL
SERIES SERVICE
MANUAL
M
FIG.
M-12—FRONT
AXLE—EARLY
MODEL
DJ-5, DJ-6
1— Outer Bearing Cone and Rollers
2— Outer Bearing Race
3—
Inner
Bearing Cone and Rollers
4—
Inner
Bearing Race 5— -Wheel Brake Cylinder
6— Bleeder Screw 7— Upper Expansion Plug
8— Steering Knuckle Pin
9— Steering Knuckle Bushing
10—
Lubrication
Fitting Opening
11—
Front
Axle I-Beam 12— Steering Knuckle Pin Bearing 13—
Brake
Backing Plate
14—
Brake
Drum 15—
Brake
Shoe
16— Wheel Hub Bolt
17— Spindle
18—
Front
Wheel Hub
19— Spindle Nut
d. Disconnect the shock absorbers at the axle
mounting
pads.
e. Disconnect the brake hydraulic
hoses
at the
connections
between
front brake
lines
and
flexible
hoses.
f. Support the axle assembly on a jack, ready for removal. g. On
vehicles
with the springs slung over the axle,
remove
the
nuts
from the spring to axle U-bolt clips,
remove
the spring clip
plates,
and slide the axle as
sembly
from underneath the vehicle.
On
vehicles
with the springs slung under the axle,
remove
the
nuts
from the spring clips and
remove
the spring clip
plates.
Then
disconnect
the spring
FIG.
M-13—FRONT
AXLE, LATE
MODEL
DJ-5, DJ-6
1— Steering Knuckle
2— Steering Knuckle Bushing
3—
Key
4— Steering Arm
5—
Lock
Spring
6—
Oil
Seal Retainer 7—
Oil
Seal
8—
Tapered
Pin
9— Dust Cover
10— Nut
11— Cotter Pin
12— Tie
Rod
13— Axle Tube 14— Plug
15— Steering Knuckle Pin
16—
Shim
17—
Thrust
Bearing
18— Bolt
19— Nut 20— Nut
21— Cotter Pin 11660
283

M
FRONT
AXLE
from
the spring shackles by removing the lower
spring
shackle bolts.
Lower
the front springs to the floor and slide the axle assembly from underneath the vehicle.
M-17. STEERING KNUCKLE SERVICE
The
following procedures are given for steering
knuckle
service when the axle is installed on the vehicle.
With
the axle removed, eliminate the ap
propriate
steps.
M-18.
Steering
Knuckle
Pin Replacement
Refer
to
Figs.
M-12, M-13.
The
only parts of the front axle, subjected to weir
which
may require replacement are the steering
knuckle
pins and bushings. To accomplish this re placement follow the procedure outlined below.
a.
Jack
up the front of the vehicle to free the
wheels.
Install
axle stands under the front axle for safety.
b.
Remove the hub cap and dust cap.
c.
Remove the wheel retaining cotter pin, nut,
and
washer.
d.
Remove the wheel with hub, bearings, and oil
retainer.
e. Disconnect the hydraulic brake tube.
f. Remove the brake backing plate. g. Remove the tapered steering knuckle pin lock.
h.
Remove the upper steering knuckle expansion
plug on early models, or the lock spring on late models.
i.
Drive the Steering
Kunckle
Pin and lower ex
pansion plug out through the bottom. When the
spindle is disassembled, do not
lose
the spacing
shim
between
the upper face of the axle and the spindle.
j.
Remove the thrust bearing and bushings,
k.
Assemble in reverse order. Be sure the oil
holes
in
the bushings are aligned with the lubrication fittings.
Ream
the bushings for running clearance
with
the steering knuckle pin.
Check
the thrust
bearing
to be sure it is not worn or damaged. When
installing
the steering knuckle pin, align the notch
for the tapered retaining pin with the pin hole.
When
assembling the knuckle, guard against lost motion
between
the axle and inner face of the
knuckle.
Adjustment is made by selective fitting
of the spacing shim
between
the upper face of the
axle and the inner face of the knuckle. Shims are
available
in the following thicknesses:
.011" [0,279 mm.] .035* [0,889 mm.] .033* [0,838 mm.]
Do not overlook bleeding the brakes after the axle
end has been reassembled. 284

'Jeep'
UNIVERSAL
SERIES
SERVICE
MANUAL
M
M-19.
SERVICE
DIAGNOSIS
SYMPTOMS
PROBABLE
REMEDY
Hard Steering
Lack
of
Lubrication
Lubricate
Tires
Soft.
. Inflate
Tight
Steering. Adjust. See "Steering" Section
Low Speed Shimmy
or
Wheel Fight
Spring
Clips and Shackles Loose
Front
Axle Shifted Insufficient Toe-In
Improper
Caster
Steering System Loose or Worn
Twisted Axle
High Speed Shimmy
or
Wheel Fight
Check
Conditions Under "Low Speed Shimmy"
Tire
Pressures Low or not
Equal
Wheel Out of Balance
Wheel Runout
Radial
Runout of Tires
Wheel Camber
Front
Springs
Settled
or Broken
Bent Steering Knuckle
Arm..................
Shock Absorbers not Effective
Steering
Gear
Loose on Frame
Front
Springs too Flexible
Tramp
Wheels Unbalanced
Wandering
Improper
Toe-in
Broken
Front Spring Main
Leaf
Axle Shifted Loose Spring Shackles or Clips
Improper
Caster
Tire
Pressure Uneven
Tightness in Steering System
Loose Wheel Bearings
Front
Spring
Settled
or Broken
Axle
Noisy
on
Pull
Pinion and Ring
Gear
Adjusted too Tight
Pinion Bearings Rough.
Axle Noisy
on
Coast
Excessive Back
Lash
at Ring and Pinion Gears.
End
Play in Pinion Shaft. . . Rough Bearing.
Axle Noisy
on
Coast
and
Pull
Ring
and Pinion Adjusted too Tight
Pinion Set too
Deep
in Ring
Gear
Pinion Bearing Loose or Worn
Back Lash
Axle Shaft Universal Joint Worn
Axle Shaft Improperly Adjusted
Worn
Differential Pinion Washers
Worn
Propeller Shaft Universal Joints.
Readjust
or Replace
Broken
Spring Center Bolt
Adjust
Reset
Adjust
or Overhaul Steering
Gear,
Front Axle or
Steering Parts
Straighten or Adjust
Inflate
Balance
Straighten Mount Properly
Same on Both Wheels
Repair
or Replace
Straighten or Replace
Replace or Repair Tighten
Over
Lubricated
Check
and Balance
Adjust—Check
for Bent Steering Knuckle Arm Replace
Spring
Center Bolt Broken
Adjust
or Replace
Reset Inflate
Adjust
Adjust
Repair
or Replace
Readjust
Replace
Readjust
Readjust
Replace
Readjust Readjust
Readjust
or Replace
Replace
Readjust
Replace
Repair
Emergency
Where difficulty is experienced with front axle differential making the vehicle inoperative,
remove
axle driving
flanges.
This will allow bringing vehicle in under its own power. Be sure the transfer
case
shift lever is in the neutral
(disengaged)
position.
285

'Jeep'
UNIVERSAL
SERIES SERVICE
MANUAL
STEERING SYSTEM
Contents
SUBJECT
PAR.
GENERAL......
O-l
Camber
Adjustment 0-9
Caster
Adjustment. .0-10
Front
Wheel Alignment Adjustments.....
.
0-6
Front
Wheel Shimmy 0-13
Front
Wheel Turning Angle Oil
Steering Knuckle Arm O-l2
Steering
Gear
Function 0-2
Steering Linkage 0-3
Toe-in
Adjustment 0-7, 8
STEERING LINKAGE SERVICE..
O-l4
Drag
Link
or Connecting Rod O-l5
Tie
Rod 0-16
Tie
Rod Removal.. O-l7
Beilcrank
Service O-l8
SUBJECT
PAR.
STEERING GEAR SERVICE
.0-22 Reassembly of Steering
Gear
0-25 Disassembly of Steering
Gear
0-24 Installation of Steering
Gear
0-26
Removal
of Steering
Gear
0-23
Steering
Gear
Adjustment. . 0-5
STEERING
COLUMN
AND
WHEEL SERVICE.
..................
.0-20
Steering Column Adjustments 0-4
Steering Wheel Installation 0-27
Steering Wheel Removal 0-21
SERVICE
DIAGNOSIS.
. 0-28
SPECIFICATIONS.
.0-29
<§>-
i©1
CJ-3B
0
0 0
®
1—
Frame
Cross Tube
(CJ-3B)
2— Steering Beilcrank Bracket
(CJ-3B)
3—
Steering Beilcrank
4—
Front
Axle Assembly 5— Steering Connecting Rod (Drag
Link)
6— Steering
Gear
Arm
7—
Steering
Gear
8—
Left
Steering Knuckle and Arm
9—
Left
Shaft and Universal Joint
FIG.
O-l—STEERING LINKAGE
10—
Left
Tie Rod Socket 11—
Left
Steering Tie Rod
12—
Left
Tie Rod Socket 13—
Right
Tie Rod Socket
14—
Beilcrank
Nut
15—
Washer
16— Bolt 17—
Beilcrank
Bearing 18—
Bearing
Spacer
(Early
Model) 19—
Washer
20—
Beilcrank
Shaft
21—
Bearing
Seal
22— Nut
23—
Lockwasher
24—
Right
Steering Tie Rod 25—
Right
Shaft and Universal Joint 26—
Right
Steering Knuckle and Arm 313

STEERING
SYSTEM
O-L
GENERAL
The
steering system on all Jeep Universal vehicles
consists of the steering gear, steering wheel, steering column and shaft, and steering linkage.
This
section covers wheel alignment, steering linkage,
steering gear, steering column and steering wheel.
0-2. Steering
Gear
Function
The
steering gear is a reducing gear. It exchanges a
relatively
large amount of movement with a small force (applied by the driver at the steering wheel), for a much smaller amount of movement with a
greatly increased force through a cam and lever
action type steering gear. The steering gear ratio is 17.9 to 1 on vehicles equipped with the F4
engine
and
19 to 1 with the V6 engine.
0-3. Steering
Linkage
Refer
to Fig. O-l.
The
steering linkage consists of a steering arm at
tached to the steering gear, a steering connecting
rod,
(drag
link),
connecting the steering arm to the
beilcrank,
and a steering tie rod connecting the
beilcrank
to the axle tie rod. The beilcrank pivots
on a pin mounted just to the left of the frame front crossmember. The steering tie rod is connected to
the beilcrank and
extends
to the right
ball
joint as sembly of tie rod. The tie rod
extends
to the wheels,
being connected to their respective steering knuckle
arms
at the wheels.
With
this linkage arrangement,
as the steering arm
moves
rearward,
the front
wheels
turn
to the left. As the steering arm
moves
forward,
the wheels
turn
to the right.
Ball
joints are used to secure the drag
link,
steering
connecting rod and tie rod ends. The
ball
joints
assist in maintaining
good
steering control and con
stant toe-in of the front wheels under all driving conditions. If the
ball
joints
become
worn enough
to allow free motion in the linkage, they should be,
replaced.
Note:
Ball
joint replacement of the tie rod requires
resetting of the wheel toe-in adjustment.
0-4.
Steering
Column
and Gear
Alignment
When
adjusting a steering gear remove all loads
from
the unit by disconnecting the steering con
necting rod (drag
link)
from the steering arm and
also
loosen
the instrument panel bracket and the
steering gear to frame
bolts
to allow the steering
post
to correctly align itself. When retightening the
steering gear to frame
bolts
use a torque wrench
pull
of 45 to 55 lb-ft. [6,2 a 7,6 kg-m.] on the
Vk*
bolts
and 30 to 40 lb-ft. [4,15 a 5,5 kg-m.] on the
Vs"
bolts. 10811
FIG.
0-2—STEERING
GEAR
1—Nut
2
—Lockwasher
3—
Steering
Gear
Arm 4—
Lever
Shaft Oil Seal
5—
Outer
Housing Bushing
6—
Inner
Housing Bushing 7—
Filler
Plug
8—
Cover
and Tube
9—
Ball
Retaining
Ring
10—Cup
11—
Ball
(Steel)
12—
Tube
and Cam
13—
Shims
14—
Upper
Cover
15—
Lockwasher
16—
Bolt
17—
Steering
Wheel 18—
Horn
Button Retainer
19—
Horn
Button
20—
Horn
Button Cap 21— Nut
22—
Spring
23—
Spring
Seat
24—
Bearing
25—
Horn
Cable
26—
Horn
Button Spring
27—
Spring
Cup
28—
Steering Column
29—
Oil
Hole
Cover
30—
Clamp
31—
Adjusting
Screw
32— Nut
33—
Bolt
34—
Side
Cover
35—
Gasket
36—
Shaft
and
Lever
37—
Housing
314

'Jeep'
UNIVERSAL
SERIES SERVICE
MANUAL
O Note:
If the steering-gear-to-frame
bolts
are not
properly
torqued, they
will
eventually
loosen
dur
ing operation of the vehicle. Loose
bolts
will
result
in
elongated
bolt
holes
making maintenance of bolt torque difficult, and may allow position of the
steering columns to be misaligned. Therefore,
proper
torquing is extremely important.
Do not tighten the steering gear to dampen out
steering trouble. Adjust the steering gear only to
remove lost motion or play within the unit.
0-5. Steering
Gear
Adjustment
The
cam and lever steering gear is illustrated in
Fig.
0-2. It consists of a
spiral
cam, and a cross shaft and lever assembly with two lever studs.
When
the steering wheel is turned, the cam
moves
the studs, causing rotary movement of the cross
shaft, which in
turn
causes angular movement of
the*steering arm.
Two
adjustments of the steering gear are necessary:
up and down play of the steering shaft, and adjustment of the lever studs (tapered pins) in the
cam
groove.
Adjustment
of the
ball
thrust bearings to eliminate up and down play of the steering shaft is ac
complished by removing shims which are installed
between
the steering gear housing and the upper
cover. Before making this adjustment
loosen
the
housing side cover adjusting screw to free the pins
in
the cam groove. Loosen the housing cover to
cut and remove a shim or more as required.
Install
the screws and tighten. Adjustment should be
made to have a slight drag but allow the steering
wheel to
turn
freely with thumb and forefinger
lightly gripping the rim.
Shims
installed for adjustment are .002*, .003", and .010"
[.0508,
.0762
and .254 mm.] in thickness.
Adjustment
of the tapered pins in the cam
groove
is accomplished by adjusting screw. Unlock the
adjusting
screw and
turn
it in until a very slight
drag
is felt through the mid-position when turning
the steering wheel slowly from one extreme position
to the other.
Backlash
of the pins in the
groove
shows up as
end play of lever shaft, also as backlash of steer ing arm.
The
cam
groove
is purposely cut shallow in the
straight
ahead driving position for each pin.
This
feature permits a
close
adjustment for normal
straight
ahead driving and provides precision steer ing and permits take up of backlash at this point
after the wear occurs without causing a bind else
where.
Always
adjust within the high range through
the mid-position of pin travel. Do not adjust off
"straight
ahead" position.
Backlash
in turned posi
tions is not objectionable.
0-6.
Front
Wheel Alignment Adjustments
To
ensure correct alignment, a definite procedure
for inspection of the steering system is recom mended. It is
suggested
that the following sequence
be used:
a.
Equalize
tire pressures and level vehicle.
b.
Check
steering gear to steering column align
ment.
c.
Inspect steering knuckle pivots, spindle, and
wheel bearing
looseness.
d.
Check
wheel runout.
e.
Test wheel balance and bearing adjustment.
f.
Check
for spring sag.
g.
Inspect brakes and shock absorbers.
h.
Check
steering gear assembly adjustment and
steering connecting rod.
i.
Check
caster,
j.
Check
toe-in.
k.
Check
toe-out
on turns.
I.
Check
camber.
m.
Check
tracking of front and
rear
wheels,
n.
Check
frame alignment.
The
factors of alignment, caster, camber, and toe-
in,
are all interrelated and if one adjustment is
made, another adjustment may be affected.
There
fore, after an alignment job is completed, make a
complete recheck of all the adjustments to be sure
the
settings
are within the limit. Be sure all front
suspension and steering system nuts and
bolts
are
all
properly torqued before taking wheel alignment readings.
Proper
alignment of front wheels must be main
tained in order to ensure
ease
of steering and satisfactory tire life.
The
most important factors of front wheel alignment are wheel camber, axle caster and wheel
toe-in.
Wheel
toe-in is the distance the wheels are closer
together
at the front than at the
rear.
Wheel
camber is the amount the wheels incline out
ward
at the top from a vertical position.
Front
axle caster is the amount in
degrees
that the
steering pivot pins are tilted towards the front or
rear
of the vehicle. Positive caster is inclination of
the top of the pivot pin towards the
rear
of the ve
hicle.
Zero caster is the vertical position of the
pivot pin. Negative or reverse caster is the in
clination
of the top of the pin towards the front
of the vehicle.
These
points should be checked at regular inter
vals,
particularly when the front axle has been
subjected to a heavy impact. When checking wheel alignment, it is important that wheel bearings and
knuckle
bearings be in proper adjustment. Loose bearings
will
affect instrument readings when
checking
the camber, pivot pin inclination and
toe-in.
To
accurately check camber and caster, use a wheel
aligning fixture.
Camber
and caster of the front
wheels are both preset.
Camber
cannot be altered
but caster can be adjusted by installing caster shims
between
the axle pad and the springs. Wheel toe-in
may
be adjusted. To measure wheel toe-in, use a
wheel aligning fixture or follow the procedure given
in Par.
0-8.
0-7.
Front Wheel Toe-in
Toe-in
as illustrated in
Fig.
0-3, is necessary to
off
set the
effect
of camber as shown in Fig. Q-4. 315

o
STEERING SYSTEM
FIG.
0-3—FRONT
WHEEL
TOE-IN
1—
Toe-in
Angle
2—
Vertical
Line
In
the absence of a wheel aligning fixture, toe-in
may
be set by measuring
between
the front wheels
at the
edge
of the rim, at the flange or at the tire
tread
center. When making this adjustment the
wheels must be in a straight ahead position.
It
is highly important that toe-in be checked regu
larly
and if found to be out of adjustment, correc tion should be made immediately.
The
correct toe-in of
these
models is found in the
specifications at the end of this section.
0-8. Toe-in Adjustment
The
toe-in may be adjusted with a line or straight
edge
as the vehicle tread is the same in front and
rear.
To set the adjustment both tie rods must be
adjusted
as outlined below:
Set the tie rod end of the steering bell-crank at
right
angles with the front axle. Place a straight
edge
or line against the left
rear
wheel and left front wheel to determine if the wheel is in a straight
ahead
position. If the front wheel tire
does
not touch the straight
edge
at both the front and
rear,
it
will
be necessary to adjust the left tie rod by loosening the clamps on each end and turning the
rod
until the tire touches the straight
edge.
Check
the right hand side in the same manner, ad
justing
the tie rod if necessary, making sure that the bell-crank remains at right angles to the axle.
When
it is determined that the front wheels are in the straight ahead position, set the toe-in by short
ening each tie rod approximately one-half
turn.
0-9.
Front
Wheel
Camber
The
purpose of camber Fig. 0-4, is to more nearly
place the weight of the vehicle over the tire con tact on the road to facilitate
ease
of steering.
The
result of excessive camber is irregular wear of
tires on outside shoulders and is usually caused by
bent axle parts.
The
result of negative or reverse camber, if ex
cessive,
will
be
hard
steering and possibly a wan
dering
condition.
Tires
will
also wear on inside shoulders. Negative camber is usually caused by
excessive wear or
looseness
of front wheel bearings, axle parts or the result of a sagging axle.
Unequal
camber may cause any or a combination
of the following conditions: unstable steering, wan- 11894-
FIG.
0-4—WHEEL CAMBER
1—Vertical
Line
2—Camber Angle
dering,
kick-back or road shock, shimmy or exces
sive tire wear. The cause of unequal camber is usu
ally
a bent steering knuckle or axle end.
Correct
wheel camber is set in the axle at the time
of manufacture and cannot be altered by any ad
justment. It is important that the camber be the same on both front wheels. Heating of any of
these
parts
to facilitate straightening usually destroys
the heat treatment given them at the factory.
Cold
bending may cause a fracture of the steel and is also
unsafe. Replacement with new parts is recom mended rather than any straightening of damaged
parts.
O-10.
Axle
Caster Caster
angle is established in the axle design by
tilting the top of the kingpin toward the
rear
and
the
bottom
of the kingpin forward so that an
imaginary
line through the center of the kingpin
would strike the ground at a point ahead of the point of tire contact.
FIG.
0-5—AXLE
CASTER
1—
Vertical
Line
2—
Caster
Angle
316

'Jeep'
UNIVERSAL SERIES SERVICE
MANUAL
The
purpose of caster Fig. O-S, is to provide steer
ing stability which
will
keep the front wheels in the
straight
ahead position and also assist in straighten
ing up the wheels when coming out of a
turn.
Caster
of the front wheels is preset. If the angle of
caster,
when accurately measured, is found to be
incorrect,
correct it to the specification given at
the end of this section by either installing new
parts
or installing caster shims
between
the axle
pad
and the springs.
If
the camber and toe-in are correct and it is known
the the axle is not twisted, a satisfactory check
may
be made by testing the vehicle on the road.
Before road testing, make sure all tires are properly
inflated,
being particularly careful that both front
tires are inflated to exactly the same pressure.
If
vehicle turns easily to either side but is
hard
to
straighten out, insufficient caster for easy handling of vehicle is indicated. If correction is necessary, it
can
usually be accomplished by installing shims
between
the springs and axle pads to secure the
desired
result.
0-11-
Front
Wheel
Turning
Angle
When
the front wheels are turned, the inside wheel
on the
turn
travels in a smaller circle than the outside wheel, therefore, it is necessary for the wheels
to toe out to prevent the tire on the inside wheel
frOm
being scuffed sideways.
This
angle for toe out
on turns is designed to permit both front wheels to
turn
on a common center by having the ends of the
steering
knuckle
arms closer
together
than the king
pins.
To
avoid possible damage to the universal joints
on the front axles of 4-wheel drive vehicles, it is advisable to check the turning angle.
Wearing
away
of the upset
edge
on the spindle housing bolt which
10607
FIG.
0-6—TURNING
ANGLE
STOP
SCREW
1—Stop
Screw
contacts the
stop
screw
will
increase the turning
angle to the point where the universal joints may
be damaged.
The
Jeep Universal Series vehicles should have a
turning
angle of not more than 27^° both left and
right.
To adjust the
stop
screw, it is necessary to
loosen
the locknut holding the
stop
screw. When
the adjustment has been made, tighten the locknut
on the screw to prevent any movement. Refer to
Fig.
O 6.
The
left steering knuckle arm controls the relation
ship of the front wheels on a left
turn
and the right
arm
controls the relation on a right
turn.
0-12. Steering
Knuckle
Arm
Should
a steering knuckle arm
become
bent, the
knuckle
housing must be replaced. It is not safe to
straighten the knuckle arm.
0-13.
Front
Wheel
Shimmy
Wheel
shimmy may be caused by various condi
tions in the wheels, axle or steering system, or a
combination of
these
conditions. Outlined below
will
be found the usual corrections of this fault:
a.
Equalize
tire pressures and see that they are
according
to specifications.
b.
Check
the wheel bearings for
looseness.
Be sure
that the inner wheel bearing race is not too
loose
on the spindle.
c.
Remove both steering knuckles and carefully inspect the upper and lower king pin bearings.
Inspect
the bearing cups for evidence of brinelling,
pitting, or fretting. Any bearings that show the slightest imperfection must be
replaced.
Reassemble
and
lubricate the front axle and steering linkage,
installing
new steering knuckle oil seals if present
seals show any wear.
d.
With
full
weight on the front wheels and one
man
working the steering play with the steering
wheel, a second man should closely observe the steering bell
crank
for any rocking motion and the
double tie rod socket for any rocking motion or
looseness
at both points. Replace the complete bell
crank
assembly if it has even the slightest rocking motion. The same applies to the double tie rod
socket.
e.
Check
wheel run-out.
This
check should include
radial
run-out and wheel
looseness
on the hub.
f- Test wheel balance—check for blowout patches,
uniform
tire tread, vulcanized tires, mud on inside
of wheels, and tires creeping on the
rims.
g.
Try
switching front wheels and tires to the
rear,
criss-crossing
them in this operation.
h.
Check
for front
spring
sag. Also check for broken
spring
leaves, broken center
spring
bolt,
loose
spring
clips
(or tight clips), over-lubrication of spring leaves, spring shackle bracket
loose
on frame, and
loose
rear
spring shackle. Be sure that the shock
absorbers
are operating properly to eliminate bobbing of the front end.
i.
Check
brakes to make sure that one
does
not
drag.
j.
Check
the steering assembly and steering con necting rod.
This
includes the up-and-down-play
of the steering worm shaft, end play of the cross 317