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Axle Bearing

A bearing that supports an axle or half shaft in an axle housing.

Axle Boot

The flexible cover that retains grease and/or oil in a transmission or a constant velocity joint.

Axle Carrier Assembly

A cast-iron framework that can be removed from the rear-axle housing for service and adjustment.

Axle Flange

The outside end of the axle where the wheel, drum and rotor attaches.

Axle Gears

Bevel gears that transfer power from the differential pinion gears to the splined axle shafts.

Axle Hop

The tendency of a live axle housing to rotate with the wheels slightly and then snap back during hard acceleration. This action may be repeated several times, creating a loss of traction until the driver releases the accelerator.

Axle Housing

The large metal container for a rear-wheel-drive vehicle's axles, differential and ring and pinion gear. (Four-wheel-drive vehicles have a similar setup at the front, as well.) The bottom of the differential, often called a pumpkin, is usually the lowest point on a vehicle.

Axle Ratio

The ratio between the rotational speed (rpm) of the drive shaft and that of the driven wheel; gear reduction through the differential, determined by dividing the number of teeth on the ring gear by the number of teeth on the drive pinion.

Axle Seat

Suspension component used to support and locate spring on the axle. Also known as a spring chair.

Axle Shaft

Alloy steel shaft that transfers torque from the differential side gears to the drive wheels. This shaft also supports vehicle weight on most passenger cars.

Axle Tamp

The tendency of a live axle housing to rotate with the wheels slightly and then snap back during hard acceleration. This action may be repeated several times, creating a loss of traction until the driver releases the accelerator.

Axle Windup

A term often used for axle tramp.

Axle-shaft End Thrust

A force exerted on the end of an axle shaft that is most pronounced when the vehicle turns corners and curves.

Axle-shaft Tubes

Tubes that are attached to the axle housing center section to surround the axle shaft and bearings.

AXOD

Automatic transaxle over drive.

AXOD-E

Automatic transaxle overdrive-electronic.

AYES

Automotive Youth Educational System (www.ayes.com)

AZC

Acronym for Automatic Zone Control Module.

Azeotrope

A mixture of two or more liquids, such as refrigerants, that when mixed in precise proportions, behave like a compound.