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SumoSprings Solo Custom Helper Springs - Rear Axle

SumoSprings Solo Custom Helper Springs - Rear Axle

Item # SSR-338-54
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1,400-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. Lowest Prices for the best vehicle suspension from SuperSprings Intl. SumoSprings Solo Custom Helper Springs - Rear Axle part number SSR-338-54 can be ordered online at or call 1-800-940-8924 for expert service.
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SuperSprings Intl Vehicle Suspension - SSR-338-54

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

1,400-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, high-density 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): 1,400 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-338-54 SuperSprings Sumo Springs Solo Rear Vehicle Suspension Kit for Vans

Installation Details SSR-338-54 Installation instructions

This Product Fits The Following Vehicles

Customer Reviews

SumoSprings Solo Custom Helper Springs - Rear Axle - SSR-338-54

Average Customer Rating:  4.7 out of 5 stars   (1378 Customer Reviews)

1,400-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.

Mercedes-Benz Sprinter

The sumo springs work great making a big difference in our converted Sprinter handling and ride.
The folks at etrailer were very helpful in us understanding and purchasing the correct springs.

2016 Mercedes-Benz Sprinter

Installed these rear SSR-338-54 and front SSF-106-47 on my 2016 Mercedes Sprinter RV conversion (Thor Citation 24SR)
Easy install. Did this myself and only had to jack up each side of the RV about 6 in. Didn't have to get the tires off the ground or removed the tires. The hardest part of the front where getting the bolts back in through the recessed hole in the suspension to bolt them in place. The rear locked right into place. Total install time about an hour. Only a short trip taken so far but sway seems to have been reduced. Will do a long trip soon to test out.

2017 Mercedes-Benz Sprinter

Made the upgrade to the Sumo Yellow on my 17 Sprinter motorhome and very happy with the results. I started with the lower weight Sumo spring and it was very good however this Yellow version makes a noticeable difference in sway and high wind resistance.


Easy to install with leveling Jacks on your vehicle (LTV UNITY RV). Lifted the rear body with the leveling Jacks and used a screw driver to pry off the bump stops. Placed the rear tab of the sumospring in and used a screw driver to force the front tap into place, almost to easy. Took only 15 minutes total if that.

2018 Mercedes-Benz Sprinter 3500

Very easy install. I used my leveling jacks to slightly raise the rear end of my RV. Quickly removed old bumpers, and snapped the Sumo Springs in place. 5 minutes per side. I had dealer quotes of $600.00 and $$1,000.00.
I spent $250.00 and couldn't be happier. The body roll is greatly reduced, and the ride feels more solid. Excellent product.

Springs still working great. This is the dingle best update I have made t o my RV.
James J - 07/15/2020


They work good. Easy 15 min install

Mercedes-Benz Sprinter

2017 Sprinter Part of the best suspension upgrade available, really helped reducing the excessive sway and roll out of our camper

2018 BMW i3

Got these for my 2018 Dynamax Isata I3. Good improvement to ride and handling so far. Quiets those loud and rough seams in the road quite a lot. Easy install, lots of how to videos out there. Worthwhile addition',good response, service and follow up from etrailer as always.


These work exactly as stated on my 2018 sprinter class C. They do not make the ride harsh at all. The yellows combined with an upgraded sway bar helped stop the sway of coming out of a driveway tremendously. Sway from wind and being passed by trucks was also greatly reduced. The addition of upgraded shocks make it so that I can drive one handed the majority of the time now. Recently had the chance to test these in a long run of coastal highway one in northern CA, they made the extremely windy road a pleasure to drive, even with the bad road conditions. Only scored a 4 and not a 5 because they do not solve all of the issues by themselves, but are an integral part of a total solution.

One year later Ive since upgraded the front suspension as well and Im still loving the ride. The idea of driving in adverse conditions no longer impacts trip planning.
Biz - 06/28/2020


Great service

2011 Mercedes-Benz Sprinter

After reading all kinds of reviews we finally broke down and ordered Sumo Springs for a 2011 Winnebago View on a Sprinter chassis. We’d been plagued with a top heavy vehicle that tended to sway and rock causing white knuckles on some of the smaller roads and the same occurred on freeways when getting passed by semis. The Sumo Springs greatly mitigated all that. Now the RV goes where I aim it in a straight line without the drama. It also rides smoother and provides some lift at the rear of the vehicle which is good because it doesn’t have much clearance. No more white knuckles and a more confident ride. etrailer ,as usual, shipped fast . They’re one of the best internet retailers you’ll find.


Sumo springs were extremely easy to install and took less than 30 minutes.. They wee installed in a Sprinter based Winnebago RV to help with the swaying of the vehicle when maneuvering over curb entrances and driveways etc. They worked well restricting the swaying of the vehicle. They have now been in for a year and the improvement in driving appears normal to me. I was weighing both the Sumo Springs and Sway Bar installation but the improvement with the Sumo springs alone was enough to avoid the beefed up sway bar modification. Very happy with the product.


Transformed the handling of my Mercedes Benz class B rv. I installed both front and rear components. The sway is greatly reduced and dive is almost eliminated entirely. I won't want to drive the rv without the components. I only wish I had put the components in from mile one. Simply put, they transformed the driving experience. Highly recommended.


Swapped out old bump stops for these in under 10 minutes, really do decrease the body roll.


Not only are the products sold by etrailer great quality but the prices and service can't be beat. One of the best places to shop online

2007 Dodge Sprinter

Timely delivery and easy installation

2016 Ram 3500

After much research, I decided on these Summo Super Springs for my 2016 Mercedes Sprinter Interstate 3500 RV. They are extremely highly rated by many people and many sources. By adding these units, there will be will additional support for our new electric bikes. Although untested, as yet, due to the "no travel" COVID virus, I am sure that the additional support on the RV frame will provide a better, safer and more comfortable ride.

2006 Winnebago View Motorhome

Excellent service, fast shipping and great product.


We took our first trip with the springs installed. We didn't notice them too much when driving, though cornering might have been easier. But we definitely felt that the vehicle was more stable when parked and leveled up. Glad we bought them!


Great product, Really made a difference on my 2020 Thor Motor Coach.


Worked good 1 month then sold the unit


We have noticed a firmer-steady road ride from our 2018 Winnebago Navion by our purchase of the Sumo Springs. We learned of this product by watching other RV owners online video's from their installation and showcasing the results by driving it down the road.

2016 Mini Countryman

Good communication


Easy, and noticeable.


Noticed the difference right away. improved the sway and the body roll as advertised. I am planning on doing the fronts next

Very happy with the rear super Sumo springs. getting ready to install the front Sumo blue middle of thes month.
Clayton - 07/03/2022
Show More Reviews

Ask the Experts about this SuperSprings Intl Vehicle Suspension

  • Recommended SumoSprings For A 2020 Jayco Melbourne 24L
    The correct weight capacity SumoSprings system for your 2020 Jayco Melbourne will depend on how much support you are looking for. If you are not getting a lot of body roll and just need a little support, go for the 900 pound # SSR-338-47. On the other hand, if you are getting a lot of body roll and or sag and need a good amount of support, the # SSR-338-54 will be the better option. With that said, the 2020 Jayco Melbourne 24L weighs just over 11,000 pounds, so the lower capacity # SSR-338-47...
    view full answer...
  • Comparing SumoSprings Solo Custom Helper Springs for a 2015 Mercedes-Benz Sprinter
    Correct, the SumoSprings Solo Custom Helper Springs part # SSR-338-47 will have a softer ride than the SumoSprings Solo Custom Helper Springs part # SSR-338-54 as it's made of a softer spring. That said, the latter will also provide more support. They are both fits for a 2015 Mercedes-Benz Sprinter
    view full answer...
  • SumoSprings For a 2020 Mercedes Sprinter 3500XD Dually Van
    I reached out to SuperSprings and they confirmed that the SumoSprings Solo Custom Helper Springs # SSR-338-54 are the correct fit for your 2020 Mercedes-Benz Sprinter 3500XD.
    view full answer...
  • Recommended SumoSprings Helper Spring for 2020 Winnebago Navion Motorhome
    The SumoSprings Solo Custom Helper Springs # SSR-338-54 is my recommendation for your 2020 Winnebago Navion motorhome. It will work well with the other components you suggested and will provide support and stability to your motorhome. They require no maintenance so they will be a great addition for you.
    view full answer...
  • Suspension Enhancement for RV on 2018 Mercedes Sprinter 3500 Chassis
    There is suspension enhancement for a 2018 Mercedes Sprinter 3500, assuming you have a 2-wheel drive and standard suspension (as opposed to the option air-ride suspension on some Weekenders), although there are no air bags or air suspension enhancements that fit. Instead, what you can use are SumoSprings, which help reduce sway, keep your vehicle level and give you a smoother ride. The correct fit for a 2018 Sprinter 3500 RV is the SumoSprings Solo Custom Helper Springs # SSR-338-54. I...
    view full answer...
  • Suspension Enhancement for 2014 Freightliner Sprinter Bluetec 2500
    The SumoSprings kit part # SSR-338-54 that you referenced would do a great job removing the sag of your 2014 Freightliner Sprinter BlueTec 2500 when loaded. Installation is pretty easy too so you'd have no problem with that.
    view full answer...
  • Recommended Bolt On Suspension Enhancement for 2013 Sprinter 3500 Chassis of Winnebago Profile View
    I recommend using the SumoSprings Solo Custom Helper Springs - Rear Axle # SSR-338-54, which will replace your factory bump stops and help support a heavy load to level your ride and minimize sway. These are a no-drill installation, so they're a not only easy to install but they're highly functional at leveling your coach and shock absorbing. I really like that SumoSprings are progressively load bearing, so they don't engage until there is a load on them and they do a great job of not stiffening...
    view full answer...
  • SumoSprings Solo that Fits 2005 Dodge Sprinter 2500
    SumoSprings does have a Solo setup that fits your 2005 Dodge Sprinter 2500 with the part # SSR-329-47 but the # SSR-338-54 does not fit your van so it would not work for you.
    view full answer...
  • Rear Suspension Enhancement Recommendation for 1981 GMC RV G3500
    Since we know your 1981 GMC Van is a G3500 we know the Timbren kit part # TGMRG35 is a confirmed fit that won't require any measuring or fabrication to install. The kit will fit as-is and works very similarly to how the SumoSprings kit works so you'd get the same amount of support.
    view full answer...
  • Suspension Enhancement Recommendation For A 2006 Dodge Sprinter 3500
    For your 2006 Dodge Sprinter 3500 I recommend the SumoSprings Solo Custom Helper Springs # SSR-338-54. This kit has a 1,400lbs capacity and will help driver control and comfort; This product measures in at 11" x 8" x 5". Unfortunately, we do not have any air bag options for your 2006 Dodge Sprinter 3500.
    view full answer...
  • Standard Duty vs Light Duty Sumo Springs for a 2018 Winnebago View 24D
    A standard duty spring like the Sumo Springs # SSR-336-54-1 is going to provide more support for your loaded 2018 Winnebago View Motorhome than a light duty spring like the # SSR-338-54, but ultimately it comes down to what your goal is when adding a suspension enhancement to your coach. These don't provide any added capacity, but are meant to help dampen some of the roughness of your ride, as well as reduce body roll and level out uneven loads that you may be carrying. If your goal is...
    view full answer...
  • Suspension Upgrade on a 2014 Thor Siesta Motorhome Built on a Mercedes Sprinter 3500 Chassis
    For your 2014 Thor Siesta Motorhome built on a Mercedes Sprinter 3500 chassis, I recommend the SumoSprings Solo Custom Helper Springs item # SSR-338-54. These helper springs have a 1,400 lbs capacity that will help lift up the back end of your motorhome while not giving you a rough bouncy feeling. The SumoSprings Maxim Custom Helper Springs item # SSR-106-47-1 you were looking at are for a 2104 Thor Siesta built on a Ford E-350 Chassis.
    view full answer...
  • SumoSprings Helper Springs That Fit 2017 Mercedes-Benz Sprinter 3500 2WD
    There is a fit for SumoSprings on your RV so long as your Sprinter motorhome is a 2017 Mercedes-Benz Sprinter 3500 with two-wheel drive. If that is the case the correct fit is the following: - SumoSprings Solo Custom Helper Springs - Rear Axle # SSR-338-54 - SumoSprings Solo Custom Helper Springs - Front Axle # SSF-106-40 These will do a fantastic job of helping minimize sway and body roll to give you a more comfortable ride in your motorhome. I have added a link below to a video review...
    view full answer...
  • SumoSprings Dimensions For a 2006 Winnebago View Motorhome On a Dodge Sprinter 3500 Chassis
    For your 2006 Winnebago View motor home on the Dodge Sprinter 3500 Chassis you will want the SumoSprings Solo Custom Helper Springs # SSR-338-54 for the rear suspension and the SumoSprings Solo Custom Helper Springs # SSF-402-54 for the front suspension. The Rear SumoSprings # SSR-338-54 are 6" tall, 4" long and 3" wide. The Front SumoSprings # SSF-402-54 are 3-1/2" tall and 2-1/2" in diameter.
    view full answer...
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  • Recommended Suspension Enhancement for a 2019 Mercedes-Benz Sprinter 3500
    I recommend using the SuperSprings SumoSprings for your 2019 Mercedes-Benz Sprinter 3500. These are a one-time installation that you never have to worry about checking up on and they provide more support (become more rigid) as you load more things into your Sprinter. For the front axle you need the kit # SSF-106-47 and then for the rear you need the kit # SSR-338-54. The SumoSprings are superior to the other suspension enhancement options because they tend to provide more cushion so your...
    view full answer...
  • Best Way to Improve Ride of 2018 Forest River MBS Motorhome on Mercedes Sprinter 3500 Chassis
    You have a really common predicament for motorhomes in that the factory anti-sway bars are just not adequate enough for the rig, and make it a white-knuckle, uncomfortable ride in winds or when passing trucks. SumoSprings like # SSR-338-54 are handy, but the best thing you can do to improve the ride of your 2018 Forest River MBS motorhome on a Mercedes-Benz Sprinter 3500 chassis is to add a better anti-sway bar, the Roadmaster Rear Anti-Sway Bar # RM-1209-131. The Roadmaster bar will work...
    view full answer...
  • Recommended SumoSprings Custom Helper Springs For 2019 Mercedes-Benz 3500
    The highest rated helper springs for the front of your 2019 Mercedes-Benz Sprinter 3500 2WD are the SumoSprings Solo Custom Helper Springs - Front Axle # SSF-106-47 which have a 1000lb load rating and do a great job of minimizing sway and body roll. Front helper springs do not need to be rated as high as added cargo/trailer weight will not affect that axle like it would the rear axle. Unfortunately you cannot use the SumoSprings Solo Custom Helper Springs - Rear Axle # SSR-338-54 or any...
    view full answer...
  • Recommended Suspension Enhancement For 2021 Dynamax Motorhome On Mercedes-Benz Sprinter 3500 Chassis
    For your 2021 Dynamax Isata 3 24FWM motorhome built on the 2019 Mercedes-Benz Sprinter 3500 chassis I recommend the SumoSprings Solo Custom Helper Springs - Rear Axle # SSR-338-54 which have a 1400lb load capacity which will do great at supporting the rear suspension while you are towing your 3200lb car, but will not negatively affect the ride quality when you are loaded lighter. If you would also like to add suspension enhancement for the front axle to prevent sway and further increase...
    view full answer...
  • Suspension Enhancements for 2017 MB Sprinter 3500 Class C
    Replacing the factory jounce springs on your 2017 Mercedes-Benz Sprinter 3500 with the SumoSprings Solo Custom Helper Springs, # SSR-338-54, is definitely an improvement over factory suspension in helping to eliminate body roll of your Class C motorhome. While I do think you would see greater improvement with installation of the Roadmaster Rear Anti-Sway Bar, # RM-1209-131 there is a variance in price to consider. The factory jounce bumper stop provides for travel prior to being engaged...
    view full answer...
  • Correct SumoSprings for Thor RV On 2020 Mercedes-Benz Sprinter 3500
    The SumoSprings Solo Custom Helper Springs part # SSF-106-47 are a great option for a 2020 Mercedes-Benz Sprinter 3500 and what I recommend using. I actually got the chance to install and use these which you can see in the video below. Then for the rear I recommend the SumoSprings Solo Custom Helper Springs part # SSR-338-54 (install video on black version below). These are the two higher rated options for this vehicle which is what I recommend for cutaways, especially if you really see...
    view full answer...
  • Recommended SumoSprings Helper Springs For a 2022 Winnebago View 24D Motorhome
    I recommend the SumoSprings Solo Custom Helper Springs # SSR-338-54 for the rear suspension and the SumoSprings Solo Custom Helper Springs # SSF-106-47 for the front axle on your 2022 Winnebago View 24D. The rear SumoSprings # SSR-338-54 are rated for 1,400lbs. The front SumoSprings # SSF-106-47 are rated for 1,000lbs. The progressive design of the SumoSprings will help to absorb a lot of the additional road shock giving you a smoother ride while also providing your suspension with...
    view full answer...
  • Sumo Springs SSF-106-47 and SSR-338-54 For 2020 PleasureWay Plateau TS
    For your 2020 PleasureWay Plateau TS RV the SumoSprings kit part # SSR-338-47 for the rear and the # SSF-106-40 are going to give you just the right amount of support to improve handling and bottoming out resistance without affecting ride quality so it would be the way to go. If you really want to improve the handling of the RV a rear sway bar upgrade like part # RM-1209-131 would be a really excellent choice. The biggest improvement you can make to the ride quality of a motorhome is a...
    view full answer...
  • SumoSprings that Fit 2005 Fleetwood Southwind 32VS
    The correct front SumoSpring kit for your 2005 Fleetwood Southwind 32VS is the SumoSpring kit part # SSF-171-40-2. And then for the rear you'd want the # SSR-187-54-1 and you'd be set.
    view full answer...
  • Recommended Bump Stop Helper Springs For 2018 Jayco Melborne Prestige 24KP Motorhome
    The Timbren # TMBRSP35A replacement bump stops are a fit for your motorhome, but the Timbren product can provide a pretty stiff ride. I'd recommend the SuperSprings Solo replacement bump stops, part # SSR-338-54. The SuperSprings Solor will offer up to 1400 lbs of support but are constructed of a more pliable material than the Timbrens, and would offer a more comfortable ride. If you click the provided link, you can see a video showing a typical install.
    view full answer...

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Info for this part was:

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Expert Research:
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Employee Cole B
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