Idler arm
Encyclopedia
On an automobile
or truck
with a conventional Parallelogram steering linkage
, the Idler Arm or idler arm assembly is a pivoting support for the steering linkage.
The idler arm consists of a rod which pivots on a bracket attached to the frame of the vehicle on one end and supports a ball joint
on the other end. Generally, an idler arm is attached between the opposite side of the center link from the Pitman arm
and the vehicle's frame to hold the center link at the proper height. Idler arms are generally more vulnerable to wear than Pitman arms because of the pivot function built into them. If the idler arm is fitted with grease fitting
s, these should be lubricated with a grease gun
at each oil change.
Automobile
An automobile, autocar, motor car or car is a wheeled motor vehicle used for transporting passengers, which also carries its own engine or motor...
or truck
Truck
A truck or lorry is a motor vehicle designed to transport cargo. Trucks vary greatly in size, power, and configuration, with the smallest being mechanically similar to an automobile...
with a conventional Parallelogram steering linkage
Parallelogram steering linkage
A parallelogram steering linkage is a steering linkage in which a pitman arm is connected to a center link. The linkage is commonly used to allow steering by hand, hence avoiding the need of any steering gear . The linkage has a parallelogram shape....
, the Idler Arm or idler arm assembly is a pivoting support for the steering linkage.
The idler arm consists of a rod which pivots on a bracket attached to the frame of the vehicle on one end and supports a ball joint
Ball joint
In an automobile, ball joints are spherical bearings that connect the control arms to the steering knuckles.More specifically, a ball joint is a steel bearing stud and socket enclosed in a steel casing. The bearing stud is tapered and threaded. It fits into a tapered hole in the steering knuckle. A...
on the other end. Generally, an idler arm is attached between the opposite side of the center link from the Pitman arm
Pitman arm
The Pitman arm is a steering component in an automobile or truck.The Pitman arm is a linkage attached to the steering gear sector shaft, that converts the angular motion of the sector shaft into the linear motion needed to steer the wheels. The Pitman arm is supported by the sector shaft and...
and the vehicle's frame to hold the center link at the proper height. Idler arms are generally more vulnerable to wear than Pitman arms because of the pivot function built into them. If the idler arm is fitted with grease fitting
Grease fitting
thumb|right|Grease nipple on a [[bearing |bearing]]A grease fitting, grease nipple, Zerk fitting, or Alemite fitting is a metal fitting used in mechanical systems to feed lubricants, usually lubricating grease, under moderate to high pressure, into a bearing using a grease gun...
s, these should be lubricated with a grease gun
Grease gun (tool)
A grease gun is a common workshop and garage tool used for lubrication. The purpose of the grease gun is to apply lubricant through an aperture to a specific point, usually on a grease fitting. The channels behind the grease nipple lead to where the lubrication is needed. The aperture may be of a...
at each oil change.