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Bell Cranks and Bell Crank/Idler Arms

There are several different components that contribute to good steering in your coach. There’s the steering wheel, coupler, two-three universal couplings, steering gear, sector shaft splines, the pitman arm, drag link, bell crank, tie rod ends and the tie rod end sleeves. But one part that is often overlooked is the bell crank arm itself, also known as an idler arm. The bell crank/idler arm attaches to the bottom of the bell crank and to the steering center link on Chevrolet/Workhorse P32 motorhome chassis. All of the pressure from the steering gear box is transmitted through the bell crank/idler arm joint on the driver’s side, which causes premature wear and contributes to excessive steering play and loose steering feel. The SuperSteer bell crank/idler arm is precision built to handle higher steering forces than its OEM counterpart. The driver’s side bell crank/idler arm utilizes tapered roller bearings top and bottom, and can be adjusted for correct end play. The passenger side bell crank/idler arm uses a ball and socket arrangement, and is built to our specifications using tighter tolerances than stock. Both bell crank/idler arms are greaseable for long life and are made right here in the USA. By the way, we no longer have a core charge on the passenger side bell crank/idler arm assemblies, as these are all new instead of rebuilt.

Here’s some interesting information about where the term “bell crank” came from. The history of the bell crank goes back to the days of large houses and plantations. It was originally developed to operate the servant’s bell. The crank would change the vertical pull on a rope to a horizontal pull on the striker of the bell. Hence, the name bell crank.

Today, bell cranks are used in many different industries. Most notably, you will find bell cranks in aircraft control systems and automotive applications. They operate in a limited space which is the big advantage to using a bell crank in mechanical systems.
In aircraft, bell cranks are commonly found in control rods, which help change the direction of the aircraft. They are often used in push-pull tube systems to decrease the length of the individual tubes, and thus the rigidity of the system.

In the automotive industry, bell cranks are used in linkage connecting systems. These different bell cranks can be used for throttle control, brake control and steering.

Of course, the most popular type of bell crank is one that is made by SuperSteer for trucks and motorhomes. It is designed to replace worn factory idle assemblies that cause excessive side-to-side movement, free play and road wander. The Super Steer bell crank will provide tighter, better steering response in your motorhome.