Get to Know Suspension Parts: A Guide from The Trailer Parts Outlet

Get to Know Suspension Parts: A Guide from The Trailer Parts Outlet

Suspension systems are one of those things you might not think about…until you need to! When working right, your suspension absorbs shocks of bumps and divots in the road. It gives you a steadier, more level ride. But when your suspension is shot, worn out, or broken, you’ll have a terrible ride. 


Most often, you’ll find a leaf spring suspension on your trailer. This could be double-eye springs or slipper springs. Commonly, slippers have more weight capacity and they are simpler. But they don’t ride quite as smoothly as double eye springs, so everything comes with a trade-off. 


Let’s get to know the parts of a suspension so you can be armed and ready with the information you need when the time comes.


Suspension Components Haulers Should Know About

There are 6 key aspects to a spring suspension setup. Depending on your axle configuration, (single axle, dual axle, triple axle) this number could vary. 

But in general, you’ll see

  1. Hangers
  2. Leaf springs
  3. Equalizers
  4. Spring seats
  5. Suspension bolts
  6. U-Bolts/U-bolt plates

Learn How Hangers Work in a Trailer Suspension System

A hanger connects the suspension system to the trailer. They connect directly to the leaf springs and equalizers. They get welded onto the trailer frame. You might have front, center or rear hangers. Fronts suspend the leaf springs closest to the tow vehicle. Centers do the equalizers while rear hangers suspend the rear end of the leaf spring. Slipper spring hangers have a space where the slipper end of the spring sits. A cylinder welded into a hanger supports the slipper, along with a bolt that goes through the hanger. Every suspension system has at least two hangers. If there are four springs in a kit, you will have 6 hangers. 

What are Equalizers in a Trailer’s Suspension?

Equalizers are suspended from the center hanger. They work as a link between the leaf springs on the multi-axle trailers. They swing from front to back and ksend weight from one axle to the other, particularly when you go over a bump. This distribution system basically evens out the burden on the trailer. If you don’t have an equalizer, bumps might break an axle by shocking it with disproportionate weight. Two connecting springs in a system always have an equalizer. 

Suspension Bolts

Your trailer suspension system has tons of moving parts. Suspension bolts hold them together. The bolts keep the springs, equalizers and hangers together. They also serve as a platform for the slipper end of the spring to rest on. 

U Bolts/U Bolt Plates

U-bolts connect the leaf springs to the axle. The U-bolt plates attach them. The U-shape lets this part connect directly to the axle. If you have square axles, you’ll need square U-bolts. The ends go over the spring seats. They are fixed to the axle with nuts. 

Need help with your suspension parts? Call The Trailer Parts Outlet

We know that your suspension can look like a confusing metal ribcage under your trailer. So we are here to help! Give us a call or drop us a written note here. We’ve seen it all when it comes to suspensions here at The Trailer Parts Outlet. So get in touch! 
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