A fundamental understanding of what is out there and how it works can still be hugely beneficial, even for experienced technicians.

Sometimes, it’s good to go back to basics. And when it comes to vehicle suspensions, understanding the types of setups out there in the vehicle fleet and their maintenance requirements can prove helpful for both seasoned technicians as well as young apprentices.

Recently, Mevotech hosted a webinar entitled: Suspension 101 – The Pros and Cons of Different Types of Suspension. The aim was to look at not only the benefits and drawbacks of different suspension system designs but also the benefits offered by installing beefier aftermarket replacement parts.

Mevotech Technical Services Manager Victor Moreira and Product Specialist Mac Chastain once again served as hosts, providing attendees with a host of valuable information in just 30 minutes.

When looking at suspension design, each requires its own diagnostic analysis and repair/replacement procedure to maintain peak performance following repairs and servicing.

Critical component

The importance of suspension in an overall vehicle’s operation is also often overlooked, particularly by consumers.

As Victor Moreira noted, the suspension is the only connection between the tires and the vehicle itself. “It pushes the tire into the road, so it’s got to maintain contact with the surface it’s travelling on,” said Moreira.

It also enables the vehicle to steer and, at the same time, cushions the vehicle and occupants from uneven and ever-changing surfaces the wheels travel on.

The earliest vehicle suspension designs were heavily based on those found on horse-drawn carts and buggies, featuring a solid beam axle.

Gradually, over time, suspension became more sophisticated. This resulted in independent front setups replacing beam axles, followed by fully independent systems, culminating in modern multi-link suspensions found on many European and increasingly, Asian and Domestic vehicles.

Types of suspension

In terms of weighing the pros and cons of different suspension types currently available, most fall into these categories:

Solid axles/beam axles

Used extensively on pickup trucks and 4×4 vehicles.

• Pros:
  • Solid axles are immensely strong and can handle the high weight and high engine torque.
  • They are simple and straightforward to repair.
• Cons:
  • Due to their design, they are not optimized for handling.
  • Traction can be compromised when cornering and the ride can be rough, as is stability at higher speeds.
  • Beam axles are similar, but have no drive function for the wheels and are often found on older, front-wheel drive vehicles

Double-wishbone (short/long-arm)

Suitable for everything from regular passenger cars to racing vehicles.

• Pros:
  • Independent suspension system that could be optimized for handling.
  • The double-wishbone design allows for optimum adjustability and tire contact.
• Cons:
  • This design takes up a considerable amount of space.
  • There are multiple adjustments and multiple wear points which adds time and cost to repairs

Twin I-beam

A variation on the independent theme and typically found on Ford trucks from the 1980s and 1990s.

• Pros:
  • Essentially a swing axle system, it can support a great deal of weight.
• Cons:  
  • Design limits overall handling compared with other independent suspension designs.

MacPherson Strut

MacPherson struts are an independent system where a lower control arm is connected to a combined damper assembly where the top pivot point of the damper is used to control motion at the top.

Most commonly found on passenger cars and crossover utilities.

• Pros:
  • A compact design and relatively few parts make this an efficient and cost-effective option for many OEMs.
• Cons:
  • Limited adjustability and torque-steer in some more powerful front-wheel-drive applications.

Multi-link

Mostly found on European and higher-end vehicles.

• Pros:
  • Designed to maximize handling and ride comfort.
• Cons:
  • Performance comes with added complexity and costs to maintain and repair.
  • Many technicians find multi-link systems among the hardest to diagnose problems on and the most challenging to fix.

Understanding types of suspension systems

For technicians, understanding the types of suspension systems out there, and how they work, can have a major impact on proficiency and quality of repairs. Of particular importance are positioning suspension components correctly when servicing them and following the correct torque procedures.

Additionally, Moreira noted that a four-wheel alignment must be performed once the repairs are completed whenever a technician is performing suspension work.

“When disassembling and reassembling, we need to make sure we do a four-wheel alignment to make sure everything’s in check and the vehicle is tracking properly.”

Alignment essential

If the alignment is not 100 percent correct, it can lead to multiple problems down the road. Such as premature wear on tires, tie rods, control arms, bushings, springs and struts.

Not only can it prove costly for the consumer to have this stuff put right, but the worn suspension can also significantly compromise the vehicle’s on-road performance and safety. And in this day and age, that’s simply not acceptable.