How to know if a torsion bar is bad?
If one corner seems to sag excessively, then that torsion bar has gone bad. Any metal object can succumb to metal fatigue over time, especially if under constant, heavy loads. Pay special attention when driving over speed bumps. If you hear a bang, then the torsion bar has grown too soft and allowed some suspension parts to come into contact.
What are the materials suitable for a torsion bar?
Torsion bars, whether they are solid or tubular, are usually highly stressed, so spring materials are normally used. MT1010 does not fit this description. Do you know what the stresses are in your design?
Is a torsion bar the same as a sway bar?
YES! Is a torsion bar the same as a sway bar? torsion bars are mounted solid to the chassis on one end and to a suspension component on the other end. They are designed to support weight. A sway bar mounts both ends to suspension components and the center to the chassis. they are designed to control body roll and do not support weight.
What is the purpose of the torsion bar?
torsion bar, rod or bar that resists twisting and has a strong tendency to return to its original position when twisted. In automobiles a torsion bar is a long spring-steel element with one end held rigidly to the frame and the other end twisted by a lever connected to the axle. It thus provides a spring action for the vehicle.
What torsion bars do?
The torsion bar is basically a length of metal rod anchored at one end to the car body and at the other end to the suspension lower link. As the wheel passes over a bump the bar twists. It returns to its original position when the bump is passed and restores the car to its normal drive height.
Do torsion bars affect ride quality?
0:568:06Cranked Torsion Bars? || That Bad?! - YouTubeYouTubeStart of suggested clipEnd of suggested clipSo it's just overall not a good situation. And we're gonna show you how it rides. All right so we'reMoreSo it's just overall not a good situation. And we're gonna show you how it rides. All right so we're driving on a fairly new concrete. Road so it's not terrible truck actually doesn't ride that bad.
Why do trucks have torsion bars?
The main advantages of a torsion bar suspension are soft ride due to elasticity of the bar, durability, easy adjustability of ride height, and small profile along the width of the vehicle. It takes up less of the vehicle's interior volume than coil springs.
How much lift can I get out of torsion bars?
About 2 to 3 inchesTorsion-bar adjustment on some applications can be attained by the turn of a wrench. About 2 to 3 inches of lift can safely be achieved by adjustment.
What is a torsion bar?
A torsion bar with a load applied. A torsion bar suspension, also known as a torsion spring suspension, is any vehicle suspension that uses a torsion bar as its main weight-bearing spring. One end of a long metal bar is attached firmly to the vehicle chassis; the opposite end terminates in a lever, the torsion key, mounted perpendicular to the bar, ...
Why do cars use torsion bars?
Some vehicles use torsion bars to provide automatic levelling, using a motor to pre-stress the bars to provide greater resistance to load and, in some cases (depending on the speed with which the motors can act), to respond to changes in road conditions.
What are the advantages and disadvantages of a torsion bar suspension?
The main advantages of a torsion bar suspension are soft ride due to elasticity of the bar, durability, easy adjustability of ride height, and small profile along the width of the vehicle. It takes up less of the vehicle's interior volume than coil springs .
What year did Jaguar E-Type have a torsion bar?
The revolutionary Jaguar E-Type introduced in 1961 had a torsion bar front suspension very similar to the Citroen and Morris Minor, and an independent coil spring rear suspension using four shock absorbers with concentric springs.
How to change ride height on torsion bars?
In most torsion bar systems, ride height (and therefore many handling features) may be changed by simply adjusting bolts that connect the torsion bars to the steering knuckles. In most cars with this type of suspension, swapping torsion bars for a different spring rate is usually an easy task.
What vehicles have torsion bars?
Torsion bar suspensions are used on combat vehicles and tanks like the T-72, Leopard 1, Leopard 2, M26 Pershing, M18 Hellcat, and the M1 Abrams (many tanks from World War II used this suspension), and on modern trucks and SUVs from Ford, Chrysler, GM, Mitsubishi, Mazda, Nissan, Isuzu, LuAZ, and Toyota. Manufacturers change the torsion bar ...
When did Torsion Bars become popular?
Torsion bars reached the height of their popularity on mass-production road cars in the middle of the 20th century at the same time that unitary construction was being adopted. At a time when the mechanics of stress and metal fatigue in monocoque body frames was poorly understood, torsion bars were very attractive to vehicle designers as the bars could be mounted to reinforced parts of the central structure, typically the bulkhead. Using MacPherson struts to achieve independent front suspension with coil springs meant providing strong turrets in the frontal structure of the car.
What is a torsion bar?
The torsion bar is basically a length of metal rod anchored at one end to the car body and at the other end to the suspension lower link. As the wheel passes over a bump the bar twists. It returns to its original position when the bump is passed and restores the car to its normal drive height. The resistance of the bar to twisting has ...
How to remove torsion bar?
Move the reaction lever forwards along the torsion bar. Next, slacken the nut holding the eyebolt through the chassis member until the suspension lowers by 12 mm Qins). Finally, remove the torsion bar by gently pulling the shoulder from the chassis housing. The reaction arm is still attached to the torsion bar. Remove it by taking off the circlip and sliding the reaction arm free.
Can you remove torsion bars from one side of car?
Before starting to remove faulty torsion bars it is important to remember that the components are handed - that is, they are not interchangeable from one side of the car to the other. If you are removing both torsion bars you should therefore keep the two sets of components separate.
Can you re-fit a torsion bar?
Re-fitting a torsion bar is the reverse of the removal method, but the following points should be noted. A new torsion bar can be fitted to either side of the car, but a used one can be fitted back only on the same side of the car.
Why do we need a torsion bar?
The flexibility of the spring is the main reason that a torsion bar is used. If a more rigid structure were used such as a steel rod were used too much load bearing pressure would be placed on the both the wheels and the under body of the vehicle.
What happens when a torsion bar is twisted?
When one end of the torsion bar is affixed to an object that cannot be moved, the other end of the bar is twisted, thus causing torque to build up. When this happens, the torsion bar is resistant to the torque and will quickly go back to its starting position once the torque is removed. In general, the object that cannot be moved is usually a frame.
Where is the adjuster bolt on a torsion bar?
Occasionally, there may be a need to adjust the height of a vehicle. This is done by using the adjuster bolt located at the frame end of the torsion bar. The weight placed on the control arm of the torsion bar in unchanged when this adjustment is made.
Why does my car feel stiff?
Once the torsion bar is manipulated in this manner, rides in the vehicle may feel somewhat stiffer. This is due to the new angle of the control arm. It is also a possibility that the adjuster bolts may have been wound too far. This causes a lack of room between the control arm of the vehicle and the upper portion of the torsion bar closest to ...
Overview
Variations
The German World War II Panther tank (and some Tigers) had double torsion bars. Needing bars longer than the width of the tank to get the required spring rate and maximum elastic bend angle from available steel alloys, designer Ernst Lehr created a suspension that effectively folded the bars in half. For each wheel, one rod was attached to the suspension arm, while another was mounted to a nearby point on the frame. On the opposite side of the tank, the two rods were atta…
Usage
Torsion bar suspensions are used on combat vehicles and tanks like the T-72, Leopard 1, Leopard 2, M26 Pershing, M18 Hellcat, and the M1 Abrams (many tanks from World War II used this suspension), and on modern trucks and SUVs from Ford, Chrysler, GM, Mitsubishi, Mazda, Nissan, Isuzu, LuAZ, and Toyota. Class 8 truck manufacturer Kenworth also offered a torsion bar suspension for its K100C and W900A models,, up to about 1980.
Advantages and disadvantages
The main advantages of a torsion bar suspension are soft ride due to elasticity of the bar, durability, easy adjustability of ride height, and small profile along the width of the vehicle. It takes up less of the vehicle's interior volume than coil springs.
Torsion bars reached the height of their popularity on mass-production road cars in the middle of the 20th century at the same time that unitary construction was being adopted. At a time when th…
Leveling
Some vehicles use torsion bars to provide automatic levelling, using a motor to pre-stress the bars to provide greater resistance to load and, in some cases (depending on the speed with which the motors can act), to respond to changes in road conditions. Height adjustable suspension has been used to implement a wheel-change mode where the vehicle is raised on three wheels so that the remaining wheel is lifted off the ground without the aid of a jack. This example is of a vehicle tha…
History
The torsion bar suspension was invented in Porsche GmbH, which patented it in 1931.
The front wheel drive Citroën Traction Avant from 1934 was the first to implement the German idea in a serially produced car, featuring independent front torsion bar suspension and a flexible trailing dead axle, also sprung by torsion bars. The flexibility of the axle beam provided wheel location features like a twist beam axle. Also in the 1930s, Porsche's prototypes of the first Volks…
Other uses
Torsion bars were sometimes used instead of conventional coil valve springs in some older motorcycles, such as the Honda CB450, and also on the Panhard Dyna X and Panhard Dyna Z cars of the 1950s. They were also used in the door mechanism of the DMC DeLorean automobile.
Bibliography
• United States Army Materiel Command (1963). "Chapter 11: The Suspension System". The Automotive Assembly: Research and Development of Materiel. Vol. 3. U.S. Government Printing Office.
• Xu, Guoying; Xue, Dabing; Wang, Tao (2017). Development and main research status of tracked vehicle suspension system (PDF). Advances in Engineering Research. Vol. 138. Academy of Armored Force Engineering.