Coil SumoSprings Custom Helper Springs for Coil Spring Suspension - Rear Axle
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2025 Ram 2500
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2025 Ram 2500
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Heavy loads or hitch-mounted gear can make factory coils struggle. These Coil SumoSprings Custom Helper Springs slide between the individual coils on your rear suspension to give the springs extra muscle. Each insert has an inner core made of microcellular polyurethane foam that cushions and supports the weight so your ride stays level and comfortable. The more you load down the rear, the stiffer the inserts become, reducing squat and keeping your handling predictable when the vehicle is working hard.
When you’re loaded up, every pothole and expansion joint gets amplified through the chassis. The microcellular foam material inside each helper spring absorbs those jolts so you don’t feel them as harshly. Because they work progressively, they firm up as weight increases, giving a controlled ride under load without making it stiff when empty. It’s a constant, self-adjusting layer of shock protection that helps defeat driver fatigue on long drives.
With extra support between your rear coils, these helper springs help cut down on body roll and bounce. That means steadier steering input, better braking stability, and more confidence when cornering or cruising through crosswinds. They help keep weight balanced across your suspension so your vehicle feels planted instead of wallowing from side to side when under load.
Unlike air bags that need hoses, valves, or compressors, these polyurethane helper springs require no maintenance or pressure checks. They simply wedge into place between your coils and go to work—no adjustments, no leaks to chase later on. The durable foam holds up to extreme temperatures, abrasion, oil, road salt, and UV exposure for lasting performance through all seasons.
Installation is simple thanks to their custom shape that matches your coil springs. Each set includes two helper springs designed for rear coil spring suspensions that are already in good working order. Once installed, they provide ongoing support without affecting your unloaded ride height or requiring periodic service—just dependable suspension help whenever you need it most.
Customer Satisfaction Score:
88% were satisfied with this product
12% of customers were not satisfied
Ratings & Reviews
Fast delivery, easy install, and you can tell the difference instantly.
Shipped quickly and easy install. We've made multiple purchases from etrailer over the last few years and always pleased. They ship quickly and the installs are easy with their directions & how to video's
These springs were a first attempt to decrease sagging with a vehicle loaded for vacation travel. They don't seem to have helped.
I have a 2015 Subaru Outback. When towing it went from a mushy rear end to a nice stiffness. Max tongue weight is 275# and with 220# on a recent trip (~2000# trailer weight) it only squatted the rear end about an inch (after rolling back and forth to let it settle).
Previously I was getting instability above 60mph especially when hitting the bumps at the ends of bridges. On my recent trip I was able to hit 80mph with the car feeling totally planted.
When totally empty you do get just the smallest hint of a 'truck like' ride but I typically carry some tools and other stuff all the time and that dampens it.
For install I found it helped to sort of feed the sumo into the coil as you kinda roll your hand over the part juming into the groove.
Just as the video and instructions show: easy to install! Took longer to jack and secure the car for installation than the installation itself. Will be giving it some test drives (with and without a load plus with my trailer to see how these perform. So focused on installing and went so quickly did not take photos
As advertised. Easy install. Increased load carrying. Like!
The CSS-1125R installation was not very easy unless you know the “trick”. Here is the trick that is not in the instructions. Trim away the inner corner of the upper slot 1/4 inch. After inserting the lower slot, pull outboard between the slots and push the edge of the upper slot under the coil to get it started. Then, using a large flat blade screw driver push inward on the upper slot radius. The slot will slide under the coil spring. Push inward to seat the slot to the coil. Move the screw driver 1/2 inch and repeat the operation.
These were really easy to install after taking off the wheels, the coils are tucked away and hard to access with the wheels on.
After reading a bunch of the reviews, I elected to put zip ties on to keep the sumo springs attached, since they don’t come with the zip ties anymore.
They reduced the sag in the rear by about an inch, helping level out the load and keeping the car planted when traveling.
Brooke M.
6/5/2025
Hey, Cail! Glad to hear that these helped to level everything out. Where are you traveling to?
Easy to install with helpful videos from etrailer on YouTube.
So far it seems to change the spring rate to reduce sagging rear-end just fine. I'm looking at putting it through its paces on a 2300-mile trip next week and hope my ride will improve.
Installed sumo springs on my 2007 Toyota Prius. They installed fairly easily in about 15 minutes per wheel. I had to trim approximately 3 inches off of each sumo spring. I used ivory soap bar to lubricate the springs before install. The rear of the car was raised maybe 2 inches as a result. I do not notice any adverse changes in the handling of the vehicle when not loaded. Moving cross country soon and need to load up vehicle so not bottoming rear springs. overall very pleased with the product. Received Quick delivery of product from etrailer.
Installed pretty easily. The trick is to start at the bottom of the spring and push it up. Didn’t need to apply any soap but springs were pretty clean to begin with (38K miles). The kit did not come with zip ties even though the etrailer description says it should, but the Sumosprings documentation clearly states they are not included.
I used the Sumo Springs on a 2014 VW Passat TDI SEL in the rear. I like the product, my car always had that overloaded look I tow a small trailer and the car's suspension was to soft.
The Sumo spring Support works great on my car the car came up about half inch and under load it gives the needed support I was locking for.
I also like that I have not to mess around with any air adjustment and it tis maintenance free.
The install was easy and I was done in about 45 minutes. The toughest part was to cut it for the instructed length for my car.
Great support for a CR-v with a heavy bike rack
Works exactly how I needed. The Ride is still very nice. There's about 350lbs with the weight of the box & rack. Suspension in the rear used to sag a bunch, even with a 2" suspension lift.
Trevor T.
10/17/2022
Ive kept them installed for the last year and the cars ride quality has never suffered. Great product!!
Very easy install. I can tell the difference in the ride of my 2021 Rav4 immediately. Looking forward to hooking up my pop up trailer with hopes the sag on the back end is much less. Good find and very excellent support by etrailer's Ashley prior to purchase and throughout up to receipt. Thank you much.
I installed these on my stock 2019 Outback hoping it would level out the rear sag when towing small teardrop trailer. Man, total game changer! Towing was fine prior to install but didn't like my headlights pointing up with rear sag.
Installation was fairly easy. I say fairly because on my Limited the springs didn't allow much room. It required using a flathead screwdriver to get them seated. Took about an hour and most of that was lifting behind removing wheels. Feels and looks 100% better without the need for new overload springs. Highly recommend
Before and after photos. One with skybox is before
Installation was easy.
Test drive showed improved handling, less sway and a better ride on bumpy roads.
Height increased by 1-1/4"
So far so good installed to mitigate droop while loaded...well see but installation was straightforward and so far goal has been met
Install was simple. On daily day to day drive it made the rear a little more firm but in most cases you won’t notice it. The rear when loaded didn’t droop as much as it did before and the ride felt more compose. Instructions were a little vague or universal but it gets the job done. Overall it did just fine. The value for what it is and what you get or don’t get from it was the biggest issue. For 200 plus dollars there are a lot more options out there that gives more adjustability and option. For some foam/rubber like materials and only for the rear, it’s on the steep side. Hopefully in the future this can be addressed and it would be worth the 5 star.
I installed a set of 1125 Sumo Springs in the rear coils of my Toyota RAV4 Limited Hybrid AWD to increase the spring rate ahead of a cross-country road trip. My RAV4 really sags with a rearward rake when passengers + rear cargo are loaded in the vehicle. This impacts the handling of the vehicle and throws off the aim of my headlights, which leads to other drivers flashing their high beams at me as my headlamps are shining in their eyes. Hopefully these Sumo Springs solve that problem. I’ve driven about 50 miles post install and can tell the ride is much more firm and stiffened up in the rear of the vehicle. The RAV4 feels much more sporty and planted.
The install was much more difficult compared to my Sienna. In our van, the Sumo Springs slid right into place - it was a 10 minute job and I didn’t need to remove the wheels. On the RAV4, this was not the case. I had to remove the rear wheels to gain enough space to work the Sumo Springs into position between the coils. The fit was also much more tight; I had to really jam the Sumos into place and slide them into the center of the coil (it was a real arm workout). The Sumo Springs also overlapped about 2”, so I removed and trimmed each down with a razor knife to achieve a ~.5” overlap (per the supplied instructions). Install time was about 90 minutes as I had to remove the Sumos and trim them - which doubled my labor time.
Time will tell to see if these work, but I’ve had a set of Sumos in my Sienna for about 15k miles / 1-year and they have done just fine, so I suspect these will too.
Put them on today. Pretty easy. Got 1/2" lift too. Gonna hookup my teardrop tomorrow to test them. See if it squats as much. Probably not. These are sooo expensive, but nothing compares.
These Sumo springs helped my 2015 CRV not sag in the rear. I carry parts and tools in the back constantly and now it rides as it should.
I installed a hitch on my Subaru Outback. These were a great addition. It added an additional 2" lift. You need to follow the directions exactly. When it says to use soap to help squeeze it in between the coils use it liberally. It takes strong hands, but once you start it's easy to wrap into the coil of the rear suspension. Great product.
2026 Subaru Outback Touring XT. The Sumo Springs installation was completed without issue. They effectively mitigate the trailer's 200 lbs. tongue weight, resulting in less than 1 inch of suspension sag. No adverse effects on handling or ride comfort have been observed. The only installation discrepancy noted involved the overlap. While most instructional videos demonstrate zero overlap, I confirmed with the manufacturer, SuperSprings, that up to 1 inch of overlap is acceptable. They ultimately advised that the units can be trimmed to preference for a customized fit and gave no definitive answer. I personally set my overlap to 1/2".
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Q
4/26/2025
One year later. Still working great, last week I was towing through a bad storm and ended up hylaning briefly in a left turn with a on the right. I managed to break out of it and of couse the vehicle was all out of sorts, however was able to stabilize the fishtail very quickly and I can confidently say that situation wouldve been a lot worse without these installed.