How Does the Rack and Pinion Steering System in Cars Work?

There are several types of steering systems available in the market. Rack and pinion steering systems are the most common. In this article, we have covered the key points that will help you better understand the steering wheel's functioning. So, let’s begin!

The rack and pinion steering system is a steering mechanism with a pair of gears responsible for converting rotatory motion into linear motion. The system consists of a pinion and a rack. The pinion is a circular gear, whereas the rack is a linear gear. 

The rotation of the pinion is responsible for turning the vehicles left or right. It is a very common component in the railways. The majority of the cars, such as small trucks and SUVs, are equipped with rack and pinion steering, unlike the larger SUVs.

The rack and pinion steering gear has two main purposes: 

• The conversion of the rotational motion of the steering wheel into linear motion 
• Reduction of gears

Basically, this system is divided into two types: 

1. End Take-Off: In this, the inner axial rods connect the tie rods to the steering rack. 
2. Centre Take-Off: Here, the tie rods are attached to the centre of the steering rack with the help of bolts. 

The gear ratio of the rack and pinion steering system is defined as the ratio of the extent the steering wheel makes the wheels turn. For instance, if the wheels turn by 20 degrees for a 360-degree turn of the steering wheel, the gear ratio comes to 18:1. 

A higher ratio indicates that you require more turns of the steering wheel to turn the wheels, whereas a lower ratio indicates less number of turns to turn the wheels. Therefore, the latter is recommended.

Now, let us look at some of the advantages of the rack and pinion steering system:

• The gearbox is easy to construct
• Economical 
• Easy to operate along with accuracy
• The contact between the steering rack and the pinion is free from play
• Internal damping is kept under check
• The idler arm and the intermediate rod are not required 

• A slight change in the design is noticed when a rack and pinion system is attached to a power steering system. In this design, a cylinder comprising a piston in the centre is placed in the rack. 
• The said piston has fluid on either of its sides. Therefore, whenever pressure is applied on the fluid on one side of the piston, it will force the piston to move. 
• This, in turn, will end up turning the rack and assist with the steering function.

Here is a list of problems that will help you to identify any problem so that you can get it repaired as soon as possible: 

• Grinding Noises: Damaged components inside the rack are responsible for the knock or chatter noise that originated from under the hood. You need to take care of this problem before your vehicle reaches 100K miles if you want to avoid expensive repairs in a few years. 
• Burning Oil Smell: The odour of the power steering fluid is similar to that of burning oil. So, if you notice this smell while driving your car, you should pull over as soon as possible. The odour of the power steering fluid indicates overheating of the gearbox, and may catch fire if the car is not stopped. 
• Power Steering Fluid Leak: The rack and pinion steering is provided with rubber seals that are responsible to stop the leaking fluid. Now, over time, these seals begin to crack and allow the water to enter the assembly, thereby causing serious damage to the components present inside. 
• Steering Lacks Response: This problem generally occurs when your tires are aligned improperly, or your vehicle has bent wheel components. This improper alignment results in uneven wear that eventually damages your steering system. You can get it repaired at a reasonable price. 

The rack and pinion steering system has revolutionised car production by making it more cost-effective. It has also improved vehicle handling along with improved gas mileage. The automobile industry has achieved a milestone with the rack and pinion steering invention. Share this with your friends and family to help them care for their vehicle!