What is the Difference Between a Torsion Beam and a Multi-Link Suspension in Cars?
3 Answers
The differences between torsion beam suspension and multi-link suspension are as follows: 1. Torsion beam suspension typically comes with trailing arms (wishbones) on both sides of the vehicle body, and the beam is used as a lateral positioning link. Due to its compact size, this type of suspension is commonly found in the rear axles of small cars, maximizing interior space. 2. Multi-link suspension evolved from double-wishbone suspension and is structurally very similar to it, making it difficult to distinguish and often influenced by original manufacturer claims. The biggest difference from torsion beam suspension is that multi-link arms can operate independently, significantly reducing the impact from road surfaces. Multi-link suspensions with three to five links offer adjustable degrees of freedom in geometric changes, allowing racing team engineers to use computer simulations for dynamic suspension tuning, enabling finer adjustments and improved stability.
When it comes to the difference between torsion beam and multi-link suspensions, let me explain from a structural perspective. The torsion beam is simply a steel beam connecting the rear wheels, like a bridge—simple, cost-effective, and space-saving, making it ideal for city driving and smooth roads. However, it tends to bounce more over bumps, with noticeable vibrations, and causes greater body roll during turns. The multi-link suspension is far more complex, featuring several independent arms controlling each wheel, which better absorbs shocks and provides a smoother ride, especially when cornering at high speeds. That said, it takes up more space, reducing trunk capacity, and adds a few thousand dollars to the car's price. In terms of maintenance, the torsion beam is cheaper and can be fixed in just over ten minutes, while repairing a multi-link requires specialized tools and higher costs. If you frequently drive on rough roads or long distances, I’d recommend the multi-link. For everyday commuting, the torsion beam is more than sufficient.
I've driven for a long time and experienced both types of suspension. The torsion beam feels stiff, makes a thudding noise over speed bumps, and jolts uncomfortably. You have to drive slower when turning, otherwise the wheels tend to skid, especially in the rain. The multi-link is softer, giving a floating sensation with excellent shock absorption that even filters out small stones, making it comfortable and safe. In terms of handling, the multi-link leads, allowing quick lane changes without body roll; the torsion beam is just about being cheap and economical. By the way, the multi-link also improves traction, making acceleration smoother; the torsion beam has slightly lower fuel consumption, making it suitable for stop-and-go traffic. For maintenance, the multi-link has fewer faults but is harder to service, requiring a specialist shop; the torsion beam allows DIY part replacements, which is quite hassle-free. In short, the choice depends on road conditions: use the torsion beam for city driving and the multi-link for highways—don’t compromise safety just to save money.
