Chrysler 300/300 Touring/300C, Dodge Magnum. Manual — part 63

DYNAMIC TOE PATTERN

Dynamic toe pattern is the inward and outward toe movement of the front and rear tires through the suspension’s
jounce and rebound travel. As the vehicle’s suspension moves up and down, the toe pattern varies. Toe pattern is
critical in controlling the directional stability of the vehicle while in motion. Front and rear dynamic toe pattern is
preset by the factory at the time the vehicle is assembled.

It is not necessary to check or adjust front or rear dynamic toe pattern when doing a normal wheel alignment. The
only time dynamic toe pattern needs to be checked or adjusted is if the frame of the vehicle has been damaged.

STEERING AXIS INCLINATION (S. A. I.)

Steering axis inclination is the angle between a true
vertical line starting at the center of the tire at the road
contact point and a line drawn through the center of
the upper ball joint (or strut) and the lower ball joint
(1). S.A.I. is built into the vehicle and is not an adjust-
able angle. If S.A.I. is not within specifications, a bent
or damaged suspension component may be the
cause.

INCLUDED ANGLE (I. A.)

Included angle (3) is the sum of the S.A.I. angle (1)
plus or minus the camber angle (2), depending on
whether or not the wheel has positive or negative
camber. If camber is positive (2), add the camber
angle to the S.A.I. angle. If camber is negative, sub-
tract the camber angle from the S.A.I. angle. Included
angle is not adjustable, but can be used to diagnose a
frame misalignment or bent suspension component
(spindle, strut).

THRUST ANGLE

Thrust angle is the averaged direction the rear wheels
are pointing in relation to the vehicle’s center line. The
presence of negative or positive thrust angle causes
the rear tires to track improperly to the left or right of
the front tires (dog tracking).

•

Negative thrust angle means the rear tires are
tracking to the left of the front tires.

•

Positive thrust angle means the rear tires are
tracking to the right of the front tires.

Improper tracking can cause undue tire wear, a lead
or pull and a crooked steering wheel. Excessive thrust
angle can usually be corrected by adjusting the rear
wheel toe so that each wheel has one-half of the total
toe measurement.

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DIAGNOSIS AND TESTING

SUSPENSION AND STEERING

CONDITION

POSSIBLE CAUSES

CORRECTION

Front End Whine On Turns

1. Defective wheel bearing

1. Replace wheel bearing

2. Incorrect wheel alignment

2. Check and reset wheel alignment

3. Worn tires

3. Replace tires

Front End Growl Or
Grinding On Turns

1. Defective wheel bearing

1. Replace wheel bearing

2. Engine mount grounding

2. Check for motor mount hitting frame
rail and reposition engine as required

3. AWD - Worn or broken C/V joint

3. Replace C/V joint

4. Loose wheel lug nuts

4. Verify wheel lug nut torque

5. Incorrect wheel alignment

5. Check and reset wheel alignment

6. Worn tires

6. Replace tires

Front End Clunk Or Snap
On Turns

1. Loose lug nuts

1. Tighten wheel lug nuts to
specifications

2. Worn or loose tie rod

2. Tighten or replace tie rod end

3. Worn or loose ball joint

3. Tighten or replace ball joint

4. Worn/loose control arm bushing

4. Replace control arm or bushing

5. Loose control arm fasteners

5. Tighten control arm fasteners to
specified torque

6. Loose stabilizer bar

6. Tighten stabilizer bar fasteners to
specified torque

7. Loose crossmember bolts

7. Tighten crossmember bolts to
specified torque

Front End Whine With
Vehicle Going Straight At A
Constant Speed

1. Defective wheel bearing

1. Replace hub and bearing assembly

2. Incorrect wheel alignment

2. Check and reset wheel alignment

3. Worn tires

3. Replace tires

Front End Growl Or
Grinding With Vehicle
Going Straight At A
Constant Speed

1. Engine mount grounding

1. Reposition engine/mount as required

Front End Clunk When
Accelerating Or
Decelerating

1. Worn or broken engine mount

1. Replace engine mount

2. Loose lug nuts

2. Tighten wheel lug nuts to specified
torque

3. Worn or loose ball joint

3. Replace ball joint/control arm

4. Worn or loose control arm bushing

4. Replace control arm or bushing

5. Loose control arm fasteners

5. Tighten fasteners to specified torque

6. Loose crossmember bolts

6. Tighten crossmember bolts to
specified torque

7. Worn tie rod end

7. Replace tie rod end

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CONDITION

POSSIBLE CAUSES

CORRECTION

Road Wander

1. Incorrect tire pressure

1. Inflate tires to recommended pressure

2. Incorrect front or rear wheel toe

2. Check and reset wheel toe

3. Worn wheel bearing

3. Replace hub and bearing

4. Worn control arm bushings

4. Replace control arm or bushing

5. Excessive friction in steering gear

5. Replace steering gear

6. Excessive friction in steering shaft
coupling

6. Replace steering intermediate
shaft/coupler

Lateral Pull

1. Unequal tire pressure

1. Inflate all tires to recommended
pressure

2. Radial tire lead

2. Perform lead correction procedure

3. Incorrect front wheel camber

3. Check and reset front wheel camber

4. Power steering gear imbalance

4. Replace power steering gear

5. Wheel braking

5. Correct braking condition causing
lateral pull

Excessive Steering Free
Play

1. Incorrect Steering Gear Adjustment

1. Replace Steering Gear

2. Worn or loose tie rod ends

2. Replace tie rod ends

3. Loose steering gear mounting bolts

3. Tighten steering gear mounting bolts
to specified torque

4. Loose or worn steering shaft coupler

4. Replace steering intermediate
shaft/coupler

Excessive Steering Effort

1. Low tire pressure

1. Inflate all tires to recommended
pressure

2. Lack of lubricant in steering gear

2. Replace steering gear

3. Low power steering fluid level

3. Fill power steering fluid reservoir to
correct level. Bleed as necessary

4. Loose drive belt

4. Replace adjuster or drive belt

5. Lack of lubricant in ball joints

5. Replace ball joints

6. Steering gear malfunction

6. Replace steering gear

7. Lack of lubricant in steering shaft
coupler

7. Replace steering intermediate
shaft/coupler

VEHICLE LEAD/PULL

To assure correct diagnosis, it is important to follow the steps outlined below in the order shown. Road test the
vehicle before and after each step to verify that the lead condition has been corrected. When evaluating a vehicle,
always drive the same road in both directions to get a feel for the effect of road crown and cross wind. A neutral
vehicle will exhibit a small amount of drift on both right and left crowned roads (normal crown sensitivity). A vehicle
with pronounced lead/pull may have one or more of the following conditions:

1. UNEQUAL TIRE PRESSURE. Adjust tire pressure to the pressure stated on door placard. Make sure the tire

pressure is equal on all four tires and evaluate the car. Also verify that the tire size and type are correct and
match each other. If the car still has a lead condition go to step (2).

2. TIRE CONICITY. Excessive tire conicity is one of the more frequent causes of vehicle lead. Cross-switch the

front tires and evaluate the car. If the car still leads in the same direction or gets worse, return the front tires to
their original position, then go to step (3).

3. SUSPENSION ALIGNMENT. Check and record the wheel alignment settings. Non-symmetrical front caster or

camber can sometimes cause a lead condition or can be used to fix a lead condition. Adjust the wheel alignment
as necessary to preferred settings (Refer to 2 - SUSPENSION/WHEEL ALIGNMENT - STANDARD PROCE-
DURE). If the car still leads, go to step (4).

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4. STEERING GEAR VALVE IMBALANCE. Steering gear valve imbalance can sometimes cause a vehicle lead.

Although there is no quick test or measurement that can be performed to verify a good or bad steering gear
valve, generally the steering efforts will feel much lighter in the lead direction and heavier in the opposite direc-
tion with an unbalanced valve. Replace the steering gear only as a

9

last resort

9

to solve the problem. To replace

the steering gear, (Refer to 19 - STEERING/GEAR - REMOVAL).

STANDARD PROCEDURE

WHEEL ALIGNMENT

PRE-WHEEL ALIGNMENT INSPECTION

Before any attempt is made to change or correct the wheel alignment, the following inspection and necessary cor-
rections must be made to ensure proper alignment.

1. Verify that the fuel tank is full of fuel. If the tank is not full, the reduction in weight will affect the curb height of

the vehicle and the alignment angles.

2. The vehicle’s passenger and luggage compartments should be free of any load that is not factory equipment.

3. Check the tires on the vehicle. All tires must be the same size and in good condition with approximately the

same amount of tread wear. Inflate all the tires to the recommended air pressure.

4. Check the wheel and tire assemblies for excessive radial runout.

5. Inspect lower ball joints and all steering linkage for looseness, binding, wear or damage. Repair as necessary.

6. Check suspension fasteners for proper torque and tighten as necessary.

7. Inspect all suspension component rubber bushings for signs of wear or deterioration. Replace any faulty bush-

ings or components before aligning the vehicle.

8. Check the vehicle’s curb height to verify it is within specifications. (Refer to 2 - SUSPENSION/WHEEL ALIGN-

MENT - STANDARD PROCEDURE - CURB HEIGHT MEASUREMENT)

WHEEL ALIGNMENT SETUP

1. Position the vehicle on an alignment rack.

2. Install all required alignment equipment on the vehicle per the alignment equipment manufacturer’s instructions.

On this vehicle, a four-wheel alignment is recommended.

NOTE: Prior to reading the vehicle’s alignment readouts, the front and rear of vehicle should be jounced
(suspension compressed/released). Induce jounce (rear first, then front) by grasping the center of the
bumper and jouncing each end of vehicle an equal number of times. The bumper should always be released
when vehicle is at the bottom of the jounce cycle.

3. Read the vehicle’s current front and rear alignment settings. Compare the vehicle’s current alignment settings to

the vehicle specifications for camber, caster and toe-in. (Refer to 2 - SUSPENSION/WHEEL ALIGNMENT -
SPECIFICATIONS)

4. If front camber and caster are not within specifications, proceed to CAMBER AND CASTER below. If caster and

camber are within specifications, proceed to TOE which can be found following CAMBER AND CASTER. Rear
camber and caster are not adjustable. If found not to be within specifications, reinspect for damaged suspension
or body components and replace as necessary. If rear toe is not within specifications, adjust rear toe before
proceeding to adjust front toe.

CAMBER AND CASTER

Camber and caster settings on this vehicle are determined at the time the vehicle is designed, by the location of the
vehicle’s suspension components. This is referred to as NET BUILD. The result is no required adjustment of camber
and caster after the vehicle is built or when servicing the suspension components. Thus, when performing a wheel
alignment, caster and camber are not normally considered adjustable angles. Camber and caster should be
checked to ensure they meet vehicle specifications.

If individual front camber or caster is found not to meet alignment specifications, each can be adjusted by shifting
the engine cradle if cross-camber and cross-caster are within specifications, or by using an available service adjust-
ment bolt package. Always try to shift the cradle first (if camber and caster are off slightly) to correct the mis-

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