Suspension System Flashcards
Describe a body over frame.
Body of the vehicle is bolted to the frame
Describe a ladder frame.
has two main rails with multiple cross members
Describe a perimeter frame.
Wider and lighter than a ladder frame, supporting the passenger compartment on the outside edges
Describe the unitized body system (unibody).
Combines frame and body together. Lighter, safer, stronger, providing greater protection to collisions.
What are the several important functions of a suspension system?
- supports the weight of the frame, body, engine, transmission, drivetrain, and passengers.
- allows rapid cornering without body roll
- keeps tires in firm contact with the road
- prevents excessive body squat
- allows wheels to turn side to side
- works with the steering system to keep wheels in correct alignment
Describe the upper and lower control arms.
Moveable lever that fastens between the frame or unibody with upper or lower ball joints to support the steering knuckle.
Describe the control arm bushings.
Bonded rubber sleeve, is part of the control arm, connects arm to Fran/body and allows movement
Describe the ball joints.
Swivel joints in the the lower and upper control arms allowing the steering knuckle to move up and down and rotate side to side.
Describe the steering knuckle.
Connects to the ball joints and provides a spindle or support for the hub, wheel bearings, brake caliber, steering linkage, wheel and tire.
Describe the stabilizer bar/sway bar.
Used to prevent the body from leaning too much on turns, attached to the body with bushings and to the lower control arm.
Describe the radius strut bar.
Connects lower control arm to the frame/unibody
What are the 4 different types of springs?
Coil spring, leaf spring, air spring, torsion bar
Describe the coil spring.
Spring steel rod wound into a spiral, found on struts or between the frame and lower control.
Describe the leaf spring.
Flat spring steel plate strips bolted together in an arc, one end anchored with a bushing to the frame, other end uses a shackle, U bolts are used to attach the springs to the axle.
Describe the air spring.
Two ply rubber cylinder that is filled with air mounted between the frame and the lower control arm or the frame and the rear axle.
How are air springs controlled?
By a manual switch or uses level sensors
Describe the torsion bar.
Large spring steel rod, on end attached to the frame other end to the upper or lower control arm.
Describe spring rate.
Refers to the stiffness or tension of the spring
Describe sprung weight.
Is the weight of the parts supported by the springs and suspension.
Describe Unsprung weight.
Is the weight of the parts not supported by the springs, wheels, tires, bearings, steering knuckle, and axle housing.
Describe a jounce bumper.
A hard rubber block that Keeps suspension from hitting the frame or struts and shocks from bottoming out.
Describe a strut.
-integrates numerous different suspension parts into one assembly
Describe a shock.
-consists of a piston in a sealed tube filled with gas and/or liquid.
Describe the shock absorber in a basic strut assembly.
Piston operating in an oil filled cylinder.
Describe the dust shield of a basic strut assembly.
Rubber cover that keeps dirt off the shock absorber rod
Describe the lower spring seat on a basic strut assembly.
Mounting place for the bottom of the coil spring.
Describe the coil spring part of a basic strut assembly.
Supports the weight of the vehicle, allows suspension action.
Describe the upper spring seat on a basic strut assembly.
Mounting place for the top of the coil spring.
Describe the strut bearing on a basic strut assembly.
Ball bearing that allows the strut assembly to rotate on steering action.
Describe the rubber bumpers on a basic strut assembly.
prevent metal on metal contact
Describe the rubber isolators on a basic strut assembly.
Prevents noise transmitting through the body
Describe the upper strut retainer on a basic strut assembly.
Mount that joins the upper end of the strut assembly to the frame or uni-body
Describe the strut rod nut on a basic strut assembly.
Nut that holds the shock rod to the upper strut retainer
Describe the gas charged strut on a basic strut assembly.
Has a low pressure gas to help prevent the oil foaming as it heats up from friction
Describe a shock absorber.
Limits up and down spring movement. Gas charged to keep oil from foaming
What are the 2 types of suspension?
Independent and non-independent
Describe a independent suspension.
Allows one wheel to move up and down with little effect on the other wheels, most common on newer vehicles.
Describe a non-independent suspension.
Up and down movement of a wheel one side will affect the other side
Describe a beam axle of a rear suspension.
Also called a dead axle is a solid rear axle beam, Uses a track bar (lateral rod) to prevent side to side movement on cornering.
Describe a semi independent suspension.
Has the right and left wheel partially independent from each other
Describe a independent rear suspension.
Is found with the rear diff mounted inside a rear subframe
Describe a long and short arm suspension.
Uses different length upper (short) and lower (long) control arms to keep the wheel from tilting in or out with suspension action
Describe a manual suspension levelling system.
Is done with manually operated switch, using an air compressor for the air springs.
Describe a automatic suspension levelling system.
Uses height sensors to activate the air compressor for the air springs.
Describe the active suspension levelling system.
Uses hydraulic rams instead of air springs, computer reacts and adjusts each ram accordingly, allows vehicle to remain level and steady.
Describe frames.
Form a common platform for attachment of all major vehicle components
Describe the purpose of springs.
Supports weight of vehicle, flexes to permit control arm and wheel assembly to move up and down
Describe the purpose of struts and shocks.
Limiting spring oscillation or dampening if the up and down compression and extension of the springs
Some struts and shocks are adjustable, how is this done?
By rotating the shock rod to open and close the oil bypass valve inside the shock
Describe a self levelling shock absorber.
Uses hydraulic lock action to maintain normal curb height
How is the rate of a spring determined?
rate is determined by the weight it takes to bend and compress.
