For the last 3 years, our fastest-selling product has been our Trailer SumoSprings. But what are they and how do they change the towing experience of your 5th wheel or bumper pull trailer? This blog will explain why this simple upgrade will change the journey when pulling your trailer, some of the data behind this suspension solution, and help you pick the right setup for your trailer.
What are Trailer SumoSprings made of?
Let’s start with how Trailer SumoSprings are made. These are not rubber; they’re made from micro-cellular polyurethane that never requires maintenance and comes with a lifetime warranty.
Because they’re not rubber, they perform differently. This solution fills the significant gap between your leaf spring suspension and the trailer frame. It’s a progressive spring providing constant load support. As a result, they remove the negative features of towing a trailer that you’re used to. This trailer upgrade reduced body roll, takes away sway, and decreases vibration. Plus, driving past a semi-truck on a two-lane highway is no longer a white-knuckle experience.
Testing Trailer SumoSprings
So why do these small bolt-on springs make such a big difference? We asked the same question which led us to test them at the Navistar Proving Grounds. Grand Design gave us a brand-new double-axle Momentum Travel Trailer towed by a 2021 Ford F-250 single-axle Super Duty truck.
We ran the trailer through some serious tests. These included a durability test over cobblestones, dirt road simulations, uneven road conditions, and various torturous road surfaces. We also simulated a freeway experience with a semi-truck pass-by, with each vehicle traveling at 60mph.
With accelerometers and a host of testing equipment measuring the spring’s performance, we wanted to gain objective data to help us understand the why behind the experience.
What we found was that when towing with the Trailer SumoSprings, the 5th wheel showed over 100% higher average displacement at every interval. What that means is that at any given point, the distance between the trailer frame and the factory suspension was on average, double. At one point, that displacement was 462% higher which shows a massive decrease in spike loading and reduces the possibility of lasting damage.
By far, our proudest result is that Trailer SumoSprings reduce G-force in the trailer by an average of 68%, as seen in the graph below. SumoSprings protect the Trailer from road vibrations causing damage to your trailer, its components, and all your contents inside.
This is the result that we hear most about because it’s what everyone with Trailer SumoSprings experiences on their journey. Get to your campsite and worry less about fixing broken shower doors and more about your vacation!
Selecting Your Trailer SumoSpring Setup
So, it’s time to choose your Trailer SumoSprings kit. There are really only two options per trailer type so it’s very simple. If you have a trailer with the axle over the spring, you’ll need our spring-under Trailer SumoSprings, which is the TSS-106 series. If you have a trailer with the axle under the spring, you’ll need our spring-over Trailer SumoSprings, which is the TSS-107 series. With each, there is a blue (-40) option for trailers with a GAWR of 3 to 5 thousand pounds, and a black (-47) option for trailers with a GAWR of 5 to 8 thousand pounds.
If your trailer’s frame is vertically off-set from the spring pack, you may need a contact plate for the installation of your Trailer SumoSprings.
Check out this video where SSI President Adam Wesiner explains what Trailer SumoSprings are and what they do.
Use our application guide to see what we have for your vehicle.