Glossary, Double reduction, Ctis – Spicer Drive Axles Application Guidelines User Manual

Page 95

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AXAG-0200 June 2009 95

Glossary

Companion Flange

- Drive shaft side of the joint that

connects the drive shaft to the drive axle.

Compressible Inserts

- Foam inserts installed in the top

and bottom of the kingpin under the cap that reduce the

pressure / vacuum that is found in the bushing area during

typical service.

Connectors, ABS

- Sealed, corrosion-resistant plugs that

link the ABS wiring system to the Electronic Control Unit

(ECU), wheel speed sensors and modulator or relay valves

using a shielded wiring harness.

Control Algorithm

- The computer commands

programmed into the Electronic Control Unit (ECU) to

control brake actuation under impending wheel lock-up.

Controlled Traction Differential

- A differential

assembly that incorporates a friction plate assembly whose

purpose is to transfer torque from the slipping wheel to the

one with traction. This assembly consists of a multiple-

disc clutch that is designed to slip when a predetermined

torque value is reached.

Cracked Drum

- Brake drum cracked all the way through

by excessive heat build-up (perhaps signifying inadequate

drum weight, and/or driver abuse and/or resurfacing of a

drum beyond the manufacturer's limit). It could also be

caused by poor brake balance (See “

Brake Balance

”)

Crack Pressure

- Minimum air pressure, expressed in

pounds per square inch (psi), required to open an air valve.

Cramp Angle

- Maximum turn of steering wheel in either

direction.

Creep Rating

- Extremely slow operation (<1.0 mi/hr)

typically applying to crane service.

Cross Link

- Composed of the adjustable cross tube and

threaded tie rod ends with ball sockets that connect the LH

knuckle tie rod arm to the RH knuckle tie rod arm.

Cross Tube

- Center tube portion of a cross link assembly

that is threaded with opposite threads on each end thereby

allowing adjustment by turning the tube with one hand.

CTIS

- Central Tire Inflation System- a means of easily

adjusting the vehicle tire pressure, both inflate and deflate,

for the conditions encountered whereby improving vehicle

mobility performance. CTIS is synonomus with military

off-road applications.

DAP (Double Anchor Pin)

- Brake system using two

pivot pins as opposed to just one for anchoring the brake

shoes.

Diagnostics, ABS

- A component-by-component self-

check performed each time the truck's ignition is turned

on. An independent microprocessor also checks the system

continuously during vehicle operation.

Diagonal System, ABS

- A brake system design that

divides the ABS into two circuits (front wheel on one side

with rear on the other side, and vice versa) to allow partial

system function should one diagonal malfunction.

Differential

- Rear axle gear assembly permitting one

axle

shaft

and wheel to turn more slowly or faster than the other

when negotiating a turn

Differential Lock

- A mechanism that eliminates the

action of the differential so that both wheels can be driven

to improve tractive efforts on slippery surfaces. See

Driver-controlled Differential Lock

”.

Digital Processing, ABS

- The latest processing

technology that is many times faster and more reliable

than analog processing.

Disc Brake

- A foundation brake system consisting of a

flat disc or rotor on either side of which are friction pads.

Equal and opposite forces are applied to these pads to

press their working surfaces into contact with the braking

path of the rotor.

Dolly

- Two-wheel trailer equipped with drawbar and the

lower portion of a fifth wheel and other components

necessary to permit a

semi-trailer

and dolly combination to

operate a full trailer; sometimes called a "PUP."

Double Anchor Pin

- See "

DAP

".

Double Diaphragm Air Chamber

- Generates force

output by utilizing two separate diaphragms, one in the

service chamber, and the other inside the spring chamber.

Double diaphragm brake chambers are the most common

in North America for general truck/

tractor

and trailer

applications. (See “

Spring Brake

”)

Double Drop

- Beam having a drop in the center between

the spring mounting pads as well as the drop from the KPI

to the spring mounting pads.

Double Reduction Axle

- Dual gear reduction generally

used in rear axles.

Draglink

- Connection between the pitman arm and the

steer ball on the steer arm. Acts as a pull-and-push rod to

convey steering movements from the chassis-mounted

steering box to the spring-mounted axle.

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