News

Shocks and Springs and Struts and Things

In the early days, things were simple. There were shock absorbers (also referred to as dampers by those wishing to seem sophisticated) and there were springs. Eventually, there were also torsion bars, but we’ll just consider them springs for these purposes. Then, gradually, struts began to appear on the scene and things got a little complicated. Not to worry, though, we’re going to break it all down today.

So what all are we talking about here?

The springs support the vehicle and separate the various bumps and imperfections of the road (or sidewalk or whatever) from the passengers who, ostensibly, prefer to travel in something with a more pleasant ride than a furniture dolly. They also have the final say in the ride height of the vehicle.

Shock absorbers, while sometimes misunderstood, work with the springs to dampen (absorb) some of the forces placed on the suspension. They prevent the suspension from bottoming out as well as wallowing like a slinky every time the vehicle drives over anything more substantial than a chewing gum wrapper. Although critical to the handling characteristics of the vehicle, shock absorbers do not have an effect on its ride height.

Drag and zoom the  diagram.

So, what is a strut then?

In the late forties, a man called Earle MacPherson discovered that incorporating the spring with the shock absorber saved a great deal of weight and complexity involved with the other suspension bits and the strut (or coil-over) suspension was born. ‘Ol Earle’s brainchild was initially cooked up for duty in compact automobiles because if its tidy size and lack of weight. Heavier-duty applications would soldier on for some time utilizing more traditional suspension setups.

A half a century or so of development later, however, and struts began to appear in light duty trucks. These days, in fact, every full-sized pickup offers a strut suspension on at least some versions. Modern struts are tough but light while offering handling as sharp and smooth as a fine cheddar.

How does a strut work?

If you check out the diagram to the right, you’ll see an artist’s (read: my) rough interpretation of a common strut suspension system found in many light duty trucks and SUVs. Go ahead and drag it around to see different angles and use your mouse wheel to zoom, it’s pretty neat.

The strut assembly connects between the lower control arm (navy blue) and the strut tower that’s rigidly attached to the frame rail (lightish grey). It consists of a shock absorber (yellow), a lower spring perch (light blue), a spring (red coil), and an upper strut hat (dark grey). Besides saving space by integrating the shock and spring, the strut pack adds a great deal of rigidity to the affair, negating the need for things like radius rods to keep the control arms in check.

Let’s get down to brass tacks. Can a strut lift?

Lifting a strut suspension certainly isn’t as simple as throwing a set of blocks under your grampa’s leaf springs but there are a host of lifting and leveling options for any budget or imagination. There are kits available with custom control arms and cross members that offer some serious height gains. The downside to that route, besides cost, is that there is often some serious disassembly and fabrication involved with the installation.

On the other end of the complicated spectrum, there are a host of lift and leveling spacers (lime green in the diagram) made for strut applications as well as height adjustable struts available from companies like Bilstein. The nice part of products like those is that installation only requires the removal of the strut assembly as opposed to a full suspension break-down. Pro tip: that coil spring is under a great deal of tension, even when the strut is removed from the vehicle, so make sure it is secured with a quality spring compressor before removing that upper strut hat.

2003-2015 Toyota 4Runner Front Suspension Lift Kit & Extended Length Pro Comp Shocks 2WD 4WD

  • 2x Front Lift Spacers
  • 2x Pro Comp Front Struts
  • Installation instructions
PRODUCT ID# 15178
$209.95$319.95

2004-2008 Ford F150 Front Suspension Lift Kit & Extended Pro Comp Struts 2WD 4WD

  • 2x Front Lift Spacers
  • 2x Front Pro Comp Extended Struts
  • Installation instructions
PRODUCT ID# 14853
$184.95$199.95

2007-2013 Chevy Avalanche Front Suspension Lift Kit & Extended Length Pro Comp Shocks 2WD 4WD

  • 2x Front Lift Spacers
  • 2x Front Pro Comp Extended Struts
  • Installation Instructions
PRODUCT ID# 14524
$299.95$334.95

2007-2015 Toyota Tundra Front Lift Kit & Extended Pro Comp Struts 2WD 4WD

  • 2x Front Lift Spacers
  • 2x Front Pro Comp Extended Struts
  • Installation instructions
PRODUCT ID# 14937
$239.95$249.95

← Previous post
Next post →