What Does A Torsion Bar Do- Let’s Get The Answer!

More or less every car owner knows that torsion bars are a simple, yet vital component within many different vehicles including cars and trucks. But in spite of its significance, what does a torsion bar do?

Torsion bars absorb the majority of road impact by twisting while maintaining the vehicle’s weight. This twisting is also referred to as torsion force. One end of the bar is primarily attached to the control arm while the other is connected to the vehicle’s chassis.

We’ll also talk about the mechanism of the torsion bar and how you can adjust it if needed. So, stay with us till the end.

What is A Torsion Bar?

Metal bars that act as a spring are known as torsion bars. The bar is tightly fastened to the frame or chassis of a vehicle at one end. Another end, depending on the configuration of the vehicle, is joined to the suspension arm, axle, or spindle.

It’s a form of the suspension system that is usually applied in wheeled vehicles such as vans, automobiles, and trucks.

According to Wikipedia,

Manufacturers change the torsion bar or key to adjust the ride height, usually to compensate for engine weight.

Besides, you can use a torsion key to modify the torsion bar on the chassis end. This modification will also change the ride height of the car. You can set up this suspension system in both the front and back, however, it’s more usually utilized in the front.

How Does a Torsion Bar Work?

Well, a torsion bar is a piece of metal that can be twisted by applying force to one end that’s connected to a moving part and another end fixed to the chassis.

It’s a fairly basic idea. For example, if you twist or bend a rod slightly, it will revert to its original shape. However, if you severely bend or twist it, it will distort and withstand a portion of the force before breaking.

Likewise, the torsion bar bends in reaction to wheel movement and deflects road shocks. After that, the torsion bar untwists and goes back to being at rest till the next shock.

 According to Hotcars,

“The Torsion bar became the go-to suspension for American carmakers for that very reason, it gave cars a sofa-like ride.”  

Moreover, the power of torsion bars comes from their ability to resist external forces. If you attach two torsion bars together and try to twist them at both ends, they won’t rotate. That’s because they’re connected together and opposing each other’s movements.

It Still Runs compares this with the control arm to better understand the function. They say,

“An example the other end of the bar will be contacted to a control arm. The control arm moves in a fixed manner on the frame and this creates the twisting movement on the bar. This, in turn, supplies the torque needed to make a spring.”

In general, the object that cannot be moved is usually a frame. If there is not any force applied to the torsion bar, it’ll stay at the same position until the force is applied.

How Can I Adjust A Torsion Bar?

Place your vehicle on a set of solid jack stands to let the suspension stay unsprung before you begin modifying a torsion bar.

Now, start on one side of the car, perform the following steps

  • Slide under your car to find the torsion bar. You’ll notice a bolt pointing upward in the mount’s center. It’d be best if you put a marking on the bolt to keep the track of revolutions you’ll make while turning the bolt.
  • If you turn the bolt clockwise, it’ll tighten increasing the load amount that can be exerted on the torsion bar.
  • Now, when you need to lower your car and accessible spring rate, you’ll have to turn the bolt counterclockwise. Typically, one full rotation of the bolt will give you a suitable result.
  • After that, retrieve your car from the jack and measure the changes in ride height.

Note: Keep in mind that the front’s two sides are to be level with one another. One side should not be taller than the other.

  • Finally, if you see that the sides aren’t equal, you’ll need to re-adjust the bolts by repeating the process from the beginning.

Frequently Asked Questions (FAQs)

What are the symptoms of a bad torsion bar?

A clunking noise will start coming from underneath your car. If you’re on a rough road, you’ll hear it more. If you notice a drop of your vehicle in one corner along with a sudden clunk, it means the torsion bar is worn out.

Can I drive with a bad torsion bar?

Yes, you can drive your car with a damaged torsion bar. However, you must proceed cautiously when turning and driving on rocky roads, as you will not have smooth control efficiency.

What if I overtighten the torsion bar?

If you overtighten your torsion bar, you’ll probably notice that your car’s ride is rougher and bumpier than usual. The excess tension will also reduce the amount of traction-maintenance capacity making it harder for you to accelerate and turn quickly.


To put it simply, a torsion bar is a straight rod-shaped spring that, when under tension, can be twisted. The two ends of the bar are joined by a mount. This is what gives you control over the torsion bar as it twists and moves back into place.

So, now you know comprehensively what does a torsion bar do. Make sure to check on it from time to time.

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