The Chrysler Royal AP1 used a modern independent front suspension with coil springs, designed to provide improved ride comfort and handling compared with earlier rigid-axle systems. Correct wheel alignment was essential for maintaining steering stability, tyre life and proper road handling.
The following service standards summarise the factory specifications used when inspecting or adjusting the front suspension and steering geometry on Chrysler Royal passenger cars.
Front Suspension Type
The Chrysler Royal AP1 front suspension uses:
Independent coil spring suspension
The system consists of upper and lower control arms, steering knuckle supports, king pins and coil springs mounted between the chassis and suspension arms.
A sway eliminator bar is mounted to the frame and connected to the lower control arms through rubber cushions to reduce body roll during cornering.
Wheel Alignment Specifications
The following wheel alignment specifications apply when the vehicle is in normal condition with no passenger load.
Camber
Specification:
± 3/8° (zero preferred)
Camber is the inward or outward tilt of the wheel when viewed from the front of the vehicle. Maintaining camber close to zero ensures even tyre wear and stable handling.
Caster
Specification:
± 1° (zero preferred)
Caster refers to the angle of the steering pivot when viewed from the side. Proper caster improves straight-line stability and steering return.
Toe-In
Specification:
0 to 1/16 inch (zero preferred)
Toe-in is the slight inward angle of the front wheels relative to each other. Proper adjustment prevents tyre scrub and ensures correct tracking.
Toe-Out on Turns
With the outer wheel turned 20 degrees, the inner wheel should turn:
20½° to 22½°
This relationship ensures correct steering geometry during cornering.
Steering Geometry Specifications
King Pin Angle
Specification:
5° to 6½°
The king pin angle contributes to steering stability and assists with steering return.
Steering Knuckle Pivot Diameter
Specification:
0.7950 inch
This dimension is important when inspecting steering knuckle components during service.
Wheel Bearing Type
The Chrysler Royal AP1 uses:
Tapered roller wheel bearings
These bearings support the front hubs and allow smooth wheel rotation while carrying vehicle load.
Wheelbase
Specification:
115 inches
The wheelbase is the distance between the front and rear axle centres and is a fundamental chassis dimension for the Chrysler Royal series.
Frame Construction
The Chrysler Royal AP1 uses a box-section frame construction, providing rigidity and durability.
The chassis frame is braced with cross members to maintain structural strength while supporting the body, suspension and drivetrain components.
Front Coil Springs
Front suspension spring specifications include:
Type: Coil springs
Inside diameter of coil: 4 inches
Static height of coil: 11 inches
Standard coil springs were fitted to most models, with heavy-duty coil springs available as optional equipment for vehicles requiring additional load capacity.
Rear Springs
Rear suspension on the Chrysler Royal AP1 uses:
Semi-elliptic leaf springs with tapered leaves
Specifications include:
Standard number of leaves: 7
Heavy duty number of leaves: 7
Spring shackles are side-strapped using rubber-bushed bolts, with rubber bushings installed between the first four leaves to reduce noise and vibration.
Shock Absorbers
Shock absorbers fitted to Chrysler Royal passenger cars include:
Rear: Oriflow double-acting telescopic
Front: Monroe double-acting telescopic
Piston diameters:
Rear: 1 inch
Front: 1⅜ inches
These hydraulic shock absorbers control suspension movement and maintain tyre contact with the road surface.
Importance of Correct Alignment
Correct suspension geometry ensures the Chrysler Royal maintains the ride quality and handling characteristics intended by Chrysler engineers.
Improper alignment can cause:
Uneven tyre wear
Steering pull or wander
Poor handling
Reduced tyre life
When restoring or servicing a Chrysler Royal AP1, alignment adjustments should always be made using the correct factory specifications.
Workshop Information
The alignment specifications above provide reference values used during servicing and inspection.
Complete suspension service procedures, adjustment methods and repair instructions are contained in OUR Workshop Manual for the Chrysler Royal AP1, available from Car Manuals Direct.
