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  1. Vehicle Suspension
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  3. Jounce-Style Springs
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SumoSprings Solo Custom Helper Springs - Rear Axle

SumoSprings Solo Custom Helper Springs - Rear Axle

Item # SSR-313-40
Our Price: $274.99
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1,000-lb Capacity. Upgrade your vehicle's rear suspension with these maintenance-free helper springs. Sturdy microcellular urethane springs cushion bumps and help support a heavy load to level your ride and minimize sway. No-drill installation. Great Prices for the best vehicle suspension from SuperSprings Intl. SumoSprings Solo Custom Helper Springs - Rear Axle part number SSR-313-40 can be ordered online at or call 1-800-940-8924 for expert service.
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SuperSprings Intl Vehicle Suspension - SSR-313-40

  • Jounce-Style Springs
  • Rear Axle Suspension Enhancement
  • Light Duty
  • SuperSprings Intl

1,000-lb Capacity. Upgrade your vehicle's rear suspension with these maintenance-free helper springs. Sturdy microcellular urethane springs cushion bumps and help support a heavy load to level your ride and minimize sway. No-drill installation.


  • Helper springs upgrade your vehicle's rear suspension for improved driver control and comfort
    • Keep your vehicle level when you're towing or hauling a heavy load
    • Help to absorb bumps and shocks
    • Minimize sway
  • Progressive load control - springs compress according to the weight of your cargo
    • Lighter loads - springs compress easily at first for soft engagement and a less bumpy ride
    • Heavier loads - springs compress by as much as 80 percent for support
  • Springs work independently from each other to compensate for off-center loads and reduce body roll during sharp turns
  • Durable microcellular urethane
    • Works in temperatures from -25 F to 200 F
    • Resists damage caused by oils, road salts, and UV rays
  • Minimal lateral expansion - springs compress vertically instead of to the sides so they aren't easily damaged when operating in tight spaces
  • Maintenance-free - no tubing to run or air pressure to monitor like with air springs
  • Simple, no-drill installation
  • 2 Jounce-style springs included
  • Made in the USA


  • Weight capacity (at 50-percent compression): 1,000 lbs
    • SumoSprings will not increase your vehicle's weight-carrying capacity
  • Limited lifetime warranty
  • 30-Day satisfaction guarantee

Rear Suspension Support

Towing or hauling a heavy load can cause rear sag as your factory suspension compresses under the weight of the load. This means that the rear axle is trying to support not only the extra load but also the weight of your vehicle. And because there is less weight on your front axle, your front tires make less contact with the road, which causes problems with traction, steering, and braking. SumoSprings upgrade your vehicle's factory suspension to level your vehicle, improve driving performance, and keep your ride comfortable.

Installed spring when it is not compressed

SumoSprings provide progressive load control - the more you load them, the stiffer they become. With a lighter load, the springs will compress easily for soft engagement and a less bumpy ride. The closed-cell urethane material allows for smooth contact between the springs and your vehicle. And the springs act like a shock absorber to dampen road vibration.

Installed spring when it is compressed

The springs can also compress by as much as 80 percent to support a heavy rear load and to help your factory suspension bear up under the load. This evens out the weight, which levels your vehicle and ensures that your front tires are making better contact with the road. A level ride means that you have improved driving control, ensures safe headlight aim, and helps to minimize sway. The springs also support your factory suspension, which helps prevent sagging and reduces bottoming out.

The springs work independently from one another to support each side of your vehicle. This action helps to reduce body roll when you make a sharp turn. This also helps compensate for an off-center load.

Durable, Custom-Fit Springs

These microcellular urethane springs are tough. They resist abrasion, oil, salt, and UV rays that can more quickly wear out other springs, and they perform well in temperatures ranging from -25 F to 200 F (-33 C to 93 C).

SumoSprings compress vertically with minimum expansion to the sides, so they won't be damaged by nearby mechanical parts and they fit safely into tighter spots. And unlike air springs, SumoSprings require no maintenance or adjustment.

The helper springs are custom designed to fit your vehicle, and they install easily - no drilling required.

SSR-313-40 SuperSprings Sumo Springs Solo Rear Vehicle Suspension Kit for Vans

Replaces SSR-308-40

Installation Details SSR-313-40 Installation instructions

This Product Fits The Following Vehicles

Video of SumoSprings Solo Custom Helper Springs - Rear Axle

Videos are provided as a guide only. Refer to manufacturer installation instructions and specs for complete information.

Video Transcript for SumoSprings Solo Rear Helper Springs Review

Hey guys, this is Jake here with etrailer. Today we're gonna be talking about the density differences in the different colors of SumoSprings. More specifically, today we're gonna be talking about the blue line of SumoSprings. So just to compare each one to start with, the blue is going to be for your lighter, more frequent use. The black is going to be a more heavier duty, constant use, and then your yellow is going to be a more extreme duty, if you're constantly towing at the max capacity of the vehicle that you're using. To go over each one a little bit more and what case is best for each one, the blue one, which is why it's most popular, is going to be for frequent towing.

If you're towing like what we've got back here, a couple of buckets of salt or if you're going to the store to pick up a load of lumber or different building materials, whatever you're hauling, if you don't have a constant load on these, these are gonna be a great option. If you're wanting to put a set of SumoSprings on, say a sprinter van that's always loaded down with tools or maybe a rigging truck that's got a welder in the back, and you just want a little bit more support than what the factory suspension can supply, the black ones are gonna be a great option if they're always engaged. The yellow is going to be your most extreme option. So if you're pushing your vehicle to its max weight capacities, the yellow's probably gonna be what you're gonna want to go with because they're gonna supply the most support if you're at that max capacity. Now focusing more in on the blue set, they are going to be made out of a softer compound, which is why they're so ideal for people who are not towing all the time because the suspension on the vehicle is designed to be soft for a comfortable ride.

Well, if you go and throw a super stiff add-on spring on there, then it's gonna completely eliminate the fact that you had a softer suspension before. So when you put these on, they're going to help to absorb the shock rather than resist it like the other ones are. For when you hit bumps, this one's going to absorb it. It'll be a soft-cushion feel, whereas those are stiffer, so they're going to hit the frame, and you're gonna feel it transfer through the vehicle. Now, being made out of a urethane material, it's going to make it quiet but still harsh.

With the blue ones they are, like I said, they're gonna be much softer. If you're not towing all the time, these are gonna be a great option to add to your vehicle because you're gonna get the support when you need it and you won't even know it's there when you don't. Now, when it comes to installation, SumoSpring does a great job of making a custom install for each vehicle that you purchase these for. For example, we installed some on this 2020 Nissan Frontier, and this lower bracket is identical to the bracket that the factory jounce bumper was bolted onto. Except this one is going to be a little bit beefier, which is always a good thing.

You want the hardware to be able to support the add-on that you're putting on there. So depending on your vehicle, you can use our fit guide to find the right SumoSpring to fit your vehicle. Let's go ahead and take this over the test course and see how the suspension performs without our SumoSprings, and then we'll get them installed. Now to start off our test course, we're gonna start with just a couple of little bumps. Oh, you can feel a lot of sag in the back end of this truck because it's already compressed, so when we go over a bump there's not much more room to travel after that. When I'm hitting these bumps, the steering on the front feels very light. The steering wheel is kind of doing whatever it wants, and we're going at low speeds too, so this is not even a, not really a true example of what you might experience on the highway with high winds or anything like that to cause sway or any other problems you might have. But this is giving us a very good example of how soft the suspension is. Even with 450 pounds in the bed, that's, I mean, that's hardly nothing for what the owner of this vehicle typically hauls with it. He hauls a heavier trailer to do some side work here and there, and he's got usually about 400 pounds on the tongue or on the trailer hitch itself. So that's a lot more leverage than just in the bed of the truck directly over the axle. So in our little slalom here, driving back and forth, you can feel a little bit of body roll side to side. So hopefully those SumoSprings are gonna help out with some of that roll and help to get this suspension a little bit more dialed in and provides more support for us. Now with our SumoSprings installed in that same 450 pounds in the bed of our truck, take another measurement, we're at 34 and a half inches, so that's only a half inch of sag compared to the inch and a half we had earlier. Now with suspension enhancement, it's designed to provide some support not get it back to that factory ride. We want to have a little bit of sag because that's how we get the correct amount of weight on our ball mount or the tongue of our trailer. For when we are going over bumps is really when it's gonna count. We're not gonna have that same drop that we had in the first run. So let's go ahead and take it through and see how the support is with our SumoSprings. To start off our test course with our SumoSprings installed, we've got that same double bump. You can tell there's a lot more support in the rear now. Now these SumoSprings are still going to be relatively soft compared to a set of Timbrens or something a little bit stiffer, but you can tell, yeah, on that double bump there, it still has that softness that we want, but it's supporting it, and that's definitely what we're looking for out of this set. Now coming around a turn, we didn't have a whole lot of body roll before, but I can definitely tell it's a little bit more solid back there. I went over some small bumps in the parking lot, and I think it's handling quite a bit better than it was before. Again, we've only got about 450 pounds in the bed, so it's not a crazy heavy load, but it's definitely enough to engage our SumoSprings to really see how they work. Now the only thing is with this kit, you're not gonna have the adjustability like you would with a set of airbags, but for the example of this neighbor of ours that owns this vehicle, he doesn't need the adjustability. He's hauling the same load all the time, and it just so happens to be a decently heavy trailer that makes his truck squat a lot more than he feels comfortable with. So this set of SumoSprings is gonna work out great for him. These are gonna be made out of a microcellular urethane, which is essentially another term for foam that has tiny little air pockets in it that allow it to flex enough but also be stiff enough to provide that support. They are also going to be a progressive spring, so the more and more they compress the stiffer they get to provide that support. There are a couple options for jounce-style replacement springs on our website. I do like these a lot because there's other types out there that are much stiffer. They may be able to hold a lot more than these can, but a lot of trucks, such as the Frontier, they don't need that much support. These being rated for 1400 pounds is more than enough support for this Frontier and what it can handle. And the reason for that is, with those stiffer springs, you almost have to be loaded to half the capacity that they can carry in order for them to give you a comfortable ride. These being that softer urethane material, when you go over a speed bump or anything unloaded, you're not gonna feel a knock up against your frame because those other springs, when they engage, since it's such a hard rubber you'll feel it every time you go over a bump or anything like that. With these, you're not hardly gonna feel it because they are that softer material. These jounce-style bumpers are gonna be for the rear of your vehicle, but if you're looking for a front-end suspension enhancement, SumoSprings does make a variety of different products for different vehicles, so be sure to check out our fit guide to see what kits are available for your vehicle if you're having an issue with your front end. Hopefully this video was able to help you decide whether or not the Blue SumoSpring line is the right one for you.

Customer Satisfaction Score:

Customer Reviews

SumoSprings Solo Custom Helper Springs - Rear Axle - SSR-313-40

Average Customer Rating:  4.7 out of 5 stars   (2085 Customer Reviews)

1,000-lb Capacity. Upgrade your vehicle's rear suspension with these maintenance-free helper springs. Sturdy microcellular urethane springs cushion bumps and help support a heavy load to level your ride and minimize sway. No-drill installation.


Drastic difference from stock bump stops. eliminates almost all extra highway sway/around turns. Beware- - is less than common for the nut that is welded in place that these thread into, breaks free and requires to be cut out via east hacksaw/flush cut. Sumo springs brand send me new, required after, nuts that made install no prob. Apparently this doesn’t happen every time? If I would have know this, I would have ordered the new nuts, just in case. Ask sumosprings about this for more info maybe? But for the price, any van carrying weight/camper needs these!


Excellent service
Davine was awesome



These Sumo Springs were easy to install, even for a 70 year old guy. I tow a 7,000lb camper and even tho I have a nice WDH I still had som sag on my Tundra. These helped level it out when towing and got rid of “some” of the bounce. They were really a godsend when I overloaded the bed with about 2,000lbs of pavers. That weight squished the Sumos significantly but the truck drove and rode great. Better and less expensive than air bags.


The SumoSprings Solo came to the RV Resort today. I installed them on my Titan SV today in less than an hour. Only drove 10 miles with them and they are what I was looking for. In my opinion it was a needed upgrade and thumbs up!


These do not fit a 2006 ram 2500. As you can see in the
Photo the bolt holes are WAY off. It also does not sit over the axle tube. My only option at this point to use them is to make a 2nd bracket to bolt the helper too. Very disappointed.


Very impressed. Stopped the Tacoma lean. Also helped with the trailer. I do use a distribution hitch I bought from etrailer. Just bought the sumo spring for other applications. Those little bitty factory bumps where junk. These help with lean, and off road hard bounce.They are great.


These springs are amazing! They helped tremendously pulling my landscape trailer with all my mowers. I picked up a tractor impliment that I would normally bring a trailer for, but decided to put these springs to the test. Couldn't believe how good my truck rode and handled with 780lbs at the rear of my bed! These springs have exceeded all expectations.
I will say that I initially put the spacer, but found it effected my ride to much so I pulled it. Afterwards it rides like stock.


First off, these won't fix worn out suspension components, they are designed to improve ride quality by reducing sag/porpoising, especially on heavier vehicles.
Our 2010 Roadtrek 210P (75k miles) is a great rv but essentially a big heavy tub going down the road. Has the tendency to lean and wallow front to back. New shocks and all suspension is good, as mentioned make sure that stuff is all in good shape.
Pics show the oem stops vs the SS stops. Big difference - you may assume ride gets harsh but not the case. The oem stops were very tired and didn't do much. The preload on the new SS stops is just about perfect - any weight changes are very progressive which takes the harshness out of the ride. I didn't really see any change to ride height either.
Road manners are improved, there's a bit more resistance to lean, but the main difference is that the front end doesn't try to change height as readily with the back end.
Not a big deal to install. Youbdont need to pull the wheels, just turn them side to side to get to the stops. Pop out the old stops and clean the retaining cups with a wire brush and some brake clean. I used syl-glyde on the new stops to help get them into place. I also used a crowbar under the stop to push it into the cup while making sure the 4 tabs captured the top of the stop. Final step was to lower the van and give it a drive, then check to ensure the fit was good. The key here is to clean the cup first and use a bit of lube on the new stop.

Very pleased and I'll be installing SS on the back end soon. Yup, they're pricey but they are good quality with a limited lifetime warranty.


These have done a great job of keeping our Ram 1500 level while pulling a trailer and having a load in the bed. No more scraping the hitch while going through dips or over bumps! The ride still feels solid.


Great product. Had them installed within 30 minutes of receiving them. Didn’t even have to jack up the truck! (2022 Ram 2500. Hopefully they perform as well as the set on my F150


I installed Sumo Springs on our 06 Xterra right after we bought our Casita 17' trailer. The back of the X squatted a bit more than I liked. I had also noticed before some tendency to bottom out if the car was full of people and stuff. These ingenious devices are a perfect solution for me! They are about 3/4" clear of being engaged with the axle when unloaded, so the ride is not overly affected, but progressively take up some of the weight when the back end starts coming down with load. It now sits very nicely with the trailer connected, no weight distributing hitch and stuff in the back, and no more bottoming. We've put a good number of miles on the X in the last year, towing and not towing, and they are still doing the job.

I should note, the back of my Xterra is lifted about an inch with AAL springs. If that were not the case, the Sumo Springs would be engaged all the time. That will vary with vehicle.

I will also note that they are non-adjustable, unlike airbags. I kinda like that, I didn't want to mess with adjusting air pressure and such. But once they do start kicking in as one or both wheels travel, they do stiffen it up quite a bit. I mean, there's no way around that; you can't take load without stiffening the suspension. As such I think they inhibit upward axle articulation a bit when 4-wheeling, but for us that's not a big deal. Since they do not connect to the axle, they don't affect downward articulation at all.

The pics are shortly after installation, one with the car unloaded, and two with trailer and gear loaded up.


I would have give it a 5star but the bolts are 1/4” I think it should be at least minimum of 3/8” or1/2” bolts to hold the sumo springs. I like them toed the camper handles very well. Wishi got these a long time ago worth getting. With out camper can tell that it’s there but rides ok. I wanted the same ride it not quite. I ask what the how high they are said 5” with bracket but it’s actually 6” with bracket see picture. I would recommend getting the sumo springs ssr-610-47.


Very easy to install from the time I walked out to the garage, gathered the tools I needed, opened the boxed , removed the or bump stops and installed, put all the tools away was 30 minutes. The attitude of the truck is noticeable from the seat. The visual ride height is slight . The ride is firm while unloaded and definitely noticeable with the trailer hooked up and no sagging. Very good good product , I recommend it!


Immediately i noticed less sway at low speed. I just did a 700 mi trip and it made my driving experience much more comfortable. Alot better control when the big rigs passed me . I spoke to several other c class rv owners that didn't have them installed and highly recommended that they do. Truly a good investment. And I am not associated with sumo springs.


I got them in 2 days. Fast shipping and delivery. I ordered the 1500# springs. The installation instructions were easy to follow. Installation of the springs was straightforward and easy. My F150 fender is at 41” unloaded. With my 1420# pin weight from my 5th wheel without the springs, my fender was at 36” and my bump stops were about 3” from the top of my Axle. With the springs installed, unloaded I have 1” until the sumo spring touches. With my 5th wheel attached, fender is at 39”. The bounce is reduced dramatically and my sumo spring is hardly compressed. I’m so excited and happy about the results! 10/10 would do again


This review is based purely on the installation. It took as long to jack up my 4Runner, place jack stands under the frame, and remove the tires as it did to install the Sumo Springs. I installed these to lessen the squat of the 4R while towing my boat and my camper (WD hitch used while towing the camper). The Sumo Springs sit just above the real axel which should greatly reduce the squat and lessen the bounce while towing. Went this route based on other 4Runner owner's reviews.


I installed the black Sumo Springs on a 2019 Toyota 4Runner. The fit was easy. Passenger side could be done without jacking the vehicle (although many folks on Youtube said they could not make the install and tighten). I used zip-ties to tie the brake sensor lines away from the pinch points. The Sumo springs are a great option. I tow a 3200# travel-trailer. The Sumos reduced sag at the hitch from 3-inches to one inch, and the wider contact points with the axle clearly provide more stability. I am 4000-miles into an out and back cross country camping trip. The ride while towing is tighter and gives more confidence. Glad I chose these over "air bags".

by: 01/31/2021

2015 Frontier Crew cab Desert Runner (purchased the yellow Sumo Springs). Easiest install ever! 18mm deep socket and long breaker bar for breaking nuts loose. Removed factory bumpstop, install sumo bracket and retighten U bolts to 58 foot pounds. After installing both brackets, lifted back of truck up 4 inches to install sumo spring with blue lock tight on bracket bolt, tighten sumo spring onto bracket and lowered truck off the jack. Overall it raised the back of my truck bed 1 inch. Ride is stiffer with no bed roll in the turns. Loaded my 24 foot travel trailer with load leveler- equalizer bars and gained 3 inches (less “squat”.) Truck is level now vs nose high (without the sumo springs). Definitely an upgrade that was needed in 2015 when I first bought the truck!!!


Came as shown, easy to install, will see how they work next time out


If you have been on the fence about whether or not to add Sumo Springs to your Isata 3. I have to say do it now, don’t wait! The ride is greatly improved and the handling is way more confident. Body roll and rocking is diminished. Going up hill over a pass, pulling a 14 foot cargo trailer, I could keep my foot into the throttle and under power through the curves instead of lifting and losing momentum. Downhill I was able to stay a little more off the brakes and drive through the corners. Yellow Sumo Spring set on the rear and black up front(cab over). Purchased from eTrailer.


Very straight forward installation. Simple. very noticeable difference under load. Towing with the gooseneck also an improvement, looking forward to the longer road trip test. So far pleased with the product and results


This set tightened up the suspension on my Mercedes motor home. Cornering is much better which helps the overall handling. I also replaced the sway bar.


Parts arrived on schedule. At first I thought that the parts did not fit my truck, so I called customer service and they immediately started to send me a return label and refund. It turned out that I was wrong, and the parts did fit. I called them back cancelled the refund action.
Great friendly service!
I also found that the price I paid was much cheaper than [online store]. I highly recommend etrailer!


Seems very robust. Looking forward to towing the trailer in the spring! Relatively easy to install, but thanks to a little [online] search, I was able to install them more easily. The steps for installation did not call for any lubrication of the top of the spring in order to get it into place, but it definitely needed it. I took multiple attempts to try and install them without and they simply wouldn't slip into place. I used a little bit of Simple Green in order to provide the lubrication that they needed to slip into place. It worked on the first attempt. OE bump-stops included in the picture next to the new Sumo Springs.

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Info for this part was:

Employee Leah B
Edited by:
Leah B
Employee Andrew K
Video by:
Andrew K
Employee Jeff D
Installed by:
Jeff D
Employee Robert C
Installed by:
Robert C
Employee Chris R
Video Edited:
Chris R
Employee Mary K
Written by:
Mary K
Employee Wilson B
Updated by:
Wilson B
Employee Alex H
Updated by:
Alex H
Employee Noah M
Updated by:
Noah M

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