1. Trailer Leaf Spring Suspension
  2. SuperSprings Intl
  3. Leaf Spring Enhancement System
  4. Springs
  5. 3000 lbs
  6. 4000 lbs
  7. 5000 lbs
SumoSprings Trailer Helper Springs w/ Line Relocation Bracket - Single Axle - 3K to 5K - Underslung

SumoSprings Trailer Helper Springs w/ Line Relocation Bracket - Single Axle - 3K to 5K - Underslung

Item # TSS-106-40
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Trailer Leaf Spring Suspension
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Lowest Prices for the best trailer leaf spring suspension from SuperSprings Intl. SumoSprings Trailer Helper Springs w/ Line Relocation Bracket - Single Axle - 3K to 5K - Underslung part number TSS-106-40 can be ordered online at etrailer.com or call 800-298-1624 for expert service.
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SuperSprings Intl Trailer Leaf Spring Suspension - TSS-106-40

  • Leaf Spring Enhancement System
  • Springs
  • 3000 lbs
  • 4000 lbs
  • 5000 lbs
  • Single Axle
  • Jounce Springs
  • SuperSprings Intl

  • Improves suspension, handling and safety
  • Progressive spring rate
    • Provides additional support as needed so you always have a smooth, comfortable ride
    • Allows the leaf spring ample movement while cushioning light loads
    • Becomes more rigid as more weight is added
      • Increases stability, providing great performance while hauling heavy loads
      • Raises trailer ride height
  • Works independently side-to-side
    • Helps compensate for off-center loads
    • Reduces body roll when swerving and turning corners
    • Works to eliminate trailer sway
  • Acts as shock absorbers, taking the brunt of bumps and rough roads
    • Reduces load on leaf spring assembly
    • Extends the life of your trailer's suspension
  • Application: 3,000-lb to 5,000-lb single, underslung axle - springs sit under axle
    • For tandem axle applications, use 2 kits
    • Designed to work with a suspension system that is in good working order
  • 2 Jounce-style springs, line relocation bracket, mounting brackets and hardware are included
    • Maintenance-free - no tubing to run or air pressure to monitor like with air springs
    • Simple, no-drill installation
  • Capacity: 500 lbs at 50 percent compression
    • Do not exceed the trailer's weight-carrying capacity
  • Spring dimensions: 4" tall x 4" diameter
    • Compresses up to 80 percent of original height with full memory rebound
  • Patented micro-cellular urethane construction
  • U-bolt dimensions:
    • 1-1/2" Tall x 2-1/2" wide
    • 4-7/8" Tall x 3" wide
  • Fits 3-leaf trailer leafsprings
  • Limited Lifetime warranty
  • 30-Day satisfaction guarantee
  • Made in the USA

TSS-106-40 SumoSprings Trailer Helper Springs with Line Relocation Bracket - Single Axle - 3K to 5K - Underslung

Installation Details TSS-106-40 Installation instructions

Customer Reviews

SumoSprings Trailer Helper Springs w/ Line Relocation Bracket - Single Axle - 3K to 5K - Underslung - TSS-106-40

Average Customer Rating:  5.0 out of 5 stars   (15 Customer Reviews)

- TSS-106-40

My order arrived quickly and correct. I appreciate the tracking emailed to me. The helpers went on easily and just like the video. My only modification was to remove the band on the rear spring. (A five minute task) The RV sits about 1 1/2 inches taller. I prefer this to flipping the axle in order to maintain a low center of gravity. In the picture, the springs actually are vertical when the RV is put back on the ground.

- TSS-106-40

These were a great addition to my creaky dual-axle boat trailer. The banging and clanging on bumps is gone, and swaying on bumps/corners is reduced as well. An excellent investment!

- TSS-106-40

My SumoSprings definitely help with trailer sway on windy days. They were not hard for me to install with standard tools.

- TSS-106-40

Got it and installed last week. Works for the trailer and I am happy with result httpsThank you Etrailer.

- TSS-106-40

the mounting bracket should be shorter

- TSS-106-40

Perfect fit for trailer with axle over leaf springs

- TSS-106-40

Got the wrong product, BUT I called and explained to Jeoff. I didn’t know if I explained it the right or the person didn’t hear me correctly? It really doesn’t matter, I just needed the right part. They are sending me a return label. Then I ordered the correct part. I’ve ordered from eTrailer before and been very happy. I very happy today, all is well

- TSS-106-40

Already installed on my Toy Hauler trailer! Super happy with them! Thank you!

- TSS-106-40

Only one on market

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Ask the Experts about this SuperSprings Intl Trailer Leaf Spring Suspension

  • Will SumoSprings Trailer Helper Springs Help With Trailer Bottoming Out
    Instead of replacing your leaf springs, the best solution for the issue you are having bottoming out is the SumoSprings Trailer Helper Springs # TSS-106-40. The reason is these will sit on the leaf spring and take the brunt of the capacity and cushion the ride, but you do need to have 7-1/2 inches of space from the leaf spring to the trailer frame. Otherwise, if you don't have that amount of space the best option would be to mount the leaf springs on top of the axle, and for that...
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  • How To Fix 2019 Vanleigh Vilano 5th Wheel Trailer Leaning To One Side
    It is indeed sometimes common for a travel trailer to lean more to one side even when new as that side usually has all of the heavier appliances. This is not really any sort of warranty issue with the leaf springs but I do have an option that should help mitigate the effect of the trailer leaning to one side and that's with the SumoSprings Trailer Helper Springs part # TSS-106-40 for underslung and part # TSS-107-40 for overslung axles. This may not get you back to level but as the springs...
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  • Recommended Sumo Springs For Small Trailer With 3500 Lb Axle With Bouncy Suspension
    It sounds like your springs are more than likely maxed out if they have a 1750 lbs capacity and your trailer is 3400 lbs loaded. Getting in the trailer and moving around is adding extra weight to the springs as well. If the leaf springs sit below the axle then you can use SumoSprings Trailer Helper Springs w/ Line Relocation Bracket part # TSS-106-40 to support the suspension and increase the stability of the leaf springs to help them last longer. Please keep in mind these are designed...
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  • Determining If SumoSprings Trailer Helper Springs Fit 2021 Coachmen 192RBS with Tandem Axles
    As long as the leaf springs on your 2021 Coachmen 192RBS are underneath the axle and not on top, then the SumoSprings Trailer Helper Springs # TSS-106-40 you were looking at will fit perfectly. The springs themselves measure right at 4" so you will have a little bit of a gap but that is alright, they will still work as designed to absorb road shock while also taking some of the load off your suspension prolonging its useable life. You will install the # TSS-106-40 with the spring...
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  • What Side of Axle Does SumoSprings Trailer Helper Springs # TSS-106-40 Install On
    You'd want to install the SumoSprings Trailer Helper Springs # TSS-106-40 on the front side of your axle.
    view full answer...
  • Raising the Height of a 2019 Forest River Viking 17BH Travel Trailer for Driveway Clearance
    Without any spacers at all the SumoSprings Trailer Helper Springs # TSS-106-40 actually sit 7-1/2" tall so there will need to be a significant amount of compression for your suspension to sit properly. I do have a better solution for the problem you are running into with your 2019 Forest River Viking 17BH. I recommend using the Dexter Trailer Springs Over-Under Conversion Kit # K71-384-00 which changes your leaf spring suspension to overslung so that your leaf springs sit on top of...
    view full answer...
  • SumoSprings Trailer Helper Springs Recommendation for OverSlung Trailer Axle
    Drop axles don't drop the distance between the trailer frame and axle as basically the drop is after the suspension and between the spindle. So the SumoSprings Trailer Helper Springs w/ Line Relocation Bracket # TSS-106-40 would install just fine on a drop axle. But sounds like you have an overslung axle based on the distance between your leaf spring and trailer frame. So for that you'd instead want the part # TSS-107-40.
    view full answer...
  • Which Side Of the Axle Do the SumoSprings Trailer Helper Springs Install
    The SumoSprings Trailer Helper Springs part # TSS-106-40 per the instructions will be installed on the side of the axle closest to the end of the leaf spring that is connected to a shackle or center link.
    view full answer...
  • Is There Anything to Isolate Trailer Shock for Bumps
    We do have a variety of products that are designed to help absorb shock from trailer movement like what you're talking about. For example, the SumoSprings Trailer Helper Springs # TSS-106-40 act like aftermarket bump stops for a vehicle but they help to cushion and add some control to your trailer suspension, but then the Curt Rebellion XD # C45949-22516 is a shock absorbing ball mount that helps to isolate trailer movement from transferring to the tow vehicle. If you can give me an...
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  • Will SumoSprings Trailer Helper Springs # TSS-106-40 Work Well on Trailer with 2,990 GVWR
    The SumoSprings Trailer Helper Springs # TSS-106-40 were intended for use on trailers with weight capacities between 3k and 5k. You are REALLY close to the range of this kit so it would work great still for you since you are 10 lbs under the ideal range.
    view full answer...
  • Recommended Suspension Enhancement for Trailer with 2-1/2 Inch Wide Leaf Springs
    I have a solution for you but because of the width of your leaf springs, the SuperSprings # TSS-106-40 are not going to be a workable solution for you since they do not make a SuperSpring to work with that size leaf spring. I would instead recommend using the Timbren Trailer Suspension Enhancement System Medium-Duty Trailers # TTRA1032 which will provide you with support for up to 7000-lbs of cargo on your single axle trailer and because the bolt directly to the trailer frame and sit above...
    view full answer...
  • How to Prevent Trailer Axle from Hitting the Frame
    Installing a 4,000 lb capacity leaf spring on a trailer with a 3,500 lb capacity axle will make the suspension stiffer which could then in turn minimize the risk of the axle contacting the frame. However, this is not what I recommend to fix your problem. Instead, I recommend using the SumoSprings Trailer Helper Springs part # TSS-106-40 which will provide you with a rubber bumper between the suspension and frame as you can see in the attached photo. They will not produce a continuous rough...
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  • SuperSprings SumoSprings For a Coachmen Apex Nano 193BHS With Single Underslung 4,400LB Axle
    The TSS-105-40 is no longer available from SuperSprings. You are going to need their current SumoSprings Trailer Helper Springs # TSS-106-40 for your Coachmen Apex Nano 193BHS. This kit is designed for underslung axles with a capacity between 3,000lbs and 5,000lbs.
    view full answer...
  • Recommended Jounce Springs for Trailer with 7K Axles
    The SumoSprings Trailer Helper Springs part # TSS-106-40 which are designed for underslung springs I can confirm will work with 7,000 lb axles. They are our best option for trailer jounce springs so this is what I recommend. They do a great job of providing additional support as needed as well as helping to reduce body roll and sway.
    view full answer...
  • Which SumoSpring Kit for Trailer Axle that is 5200 lb and Underslung
    Since you have a 5,200 lb underslung axle the correct SumoSprings kit would be the part # SS33HR as the kit you mentioned would be rated too low. Normally you would install this on the front side of the axle. We have also confirmed that this works with slipper springs as well.
    view full answer...
  • Recommended SumoSprings Trailer Helper Springs For Trailer With 3500lb Tandem Axles
    Since your trailer has tandem 3500lb axles the correct SumoSprings Trailer Helper Springs is the # TSS-106-40 if your leaf springs are underneath the axles, or the # TSS-107-40 if your leaf springs are on top of the axles. Both of these kits are designed for axles rated from 3000-5000lbs which is perfect for your trailer, and will fight trailer sway and body roll while also providing support to your suspension to increase its working life. I included videos of the products mentioned...
    view full answer...
  • Where To Install SumoSprings Trailer Helper Springs TSS-106-40 On Trailer With Tandem 3500lbs Axles
    You got it! When installing the SumoSprings Trailer Helper Springs # TSS-106-40 on your trailer with tandem 3500lb axles the helper spring will get installed in the front part of the rear axle closer to the equalizer, and on the rear part of the front axle also closer to the equalizer. Keep in mind this kit only includes enough helper springs for a single axle so since you have tandem axles you will need two kits. I included a video review of the # TSS-106-40 for you to take a look at.
    view full answer...
  • Suspension Enhancement For Light 5th Wheel Trailer Rocking Side-to-Side When Towing
    There is going to be some rocking back and forth on uneven pavement, and while it isn't a good or bad thing for the structure as the leaf springs are designed to take on that movement, it can create a bit of an issue with handling, so the best thing to do is add some simple suspension enhancement for the trailer. The best option are SumoSprings, as they will cushion the load and improve stability to help eliminate the side-to-side movement, or body roll you are experiencing. It looks...
    view full answer...
  • Recommended SumoSpring To Supplement The Suspension On A Boat Trailer
    The SumoSprings Trailer Helper Springs # TSS-106-40 will definitely help take some of the strain off your suspension system. These are starting to get a lot more popular as they are usually less expensive and require a lot less work to get installed than a shock type system. As an added bonus, these can also help prevent body roll and assist with sway issues, so they are highly recommended. Being American made is just one more plus with SumoSprings in a pretty long list of positives...
    view full answer...
  • Will SumoSprings Trailer Helper Springs Increase Space Between Frame and Axle
    The SumoSprings Trailer Helper Springs typically install compressed so they do tend to provide more space between the frame and axle in most cases but not by much and this is not really the goal of the system. If you don't have enough space between the frame and axle then this may be due to worn out leaf springs so I recommend checking this but I have attached the SumoSpring options below which are based on axle type and capacity. SumoSprings Trailer Helper Springs w/ Line Relocation...
    view full answer...
  • SumoSprings for KZ Sportsmen Dual Axle Travel Trailer
    The SumoSprings Trailer Helper Springs # TSS-107-40 are designed for single axle trailer applications, so for your tandem axle travel trailer, you'll just need two of these kits. These SumoSprings will fit your 2016 KZ Sportmen travel trailer as long as each of the axles is rated between 3,000 lbs and 5,000 lbs and they are overslung, where the springs sit on top of the axle. If your springs sit below the axle, which is the more common setup, you'll want to use two of part # TSS-106-40,...
    view full answer...
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  • Will the SumoSprings Trailer Helper Springs Fit a 2020 Keystone Cougar?
    The SumoSprings Trailer Helper Springs part # TSS-107-40 are compatible with practically any trailer that has a 3K to 5K overslung axle or in other words the leaf springs are mounted on top of the axle. If you have an underslung axle in which the leaf springs are mounted below the axle then you need the SumoSprings Trailer Helper Springs part # TSS-106-40 which is also designed for 3K to 5K capacity axles. I spoke with SuperSprings and they informed me that there isn't a minimum space...
    view full answer...
  • Correct SumoSprings Solo Custom Helper Springs for a Travel Trailer
    I do have an option for you but if you're looking to install SumoSprings on a travel trailer you'll be looking at either the SumoSprings Trailer Helper Springs part # TSS-107-40 for overslung axles or part # TSS-106-40 for underslung axles. They have a 3,000 lb to 5,000 lb capacity. These systems both install by attaching to the leaf springs.
    view full answer...
  • Can the Leaf Springs Be Upgraded On a Lippert 3,500 Lb Axle
    It is possible to upgrade the leaf springs on a trailer to a higher rated set but I do not recommend this as it can create a rough ride. The better option would be to install the SumoSprings Trailer Helper Springs part # TSS-107-40 for overslung or part # TSS-106-40 for underslung axles. These will offer both additional support without decreasing the ride quality. If you would still like for me to recommend a set of upgraded leaf springs, I'd need to know the unloaded length from eye to eye.
    view full answer...
  • Recommended Trailer Suspension to Dampen Road Shock
    Based on what you are saying and your photos, it apprears you have springs that are double eye springs. The springs will need to be based on the load of your trailer. The axle capacity may be difficult to know as you said it appears to be custom. I recommend determining the full capacity of the trailer including the wood you will be adding to it. Once you know that complete weight, then I can help you determine the best springs for your total capacity. Overbuilt isn't bad in...
    view full answer...
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  • What Causes Trailer Leaf Springs To Break Continuously
    Yes, leaf springs must be replaced in pairs which is why one side left go and then the other shortly after. In regards to the stent you get on a full set of leaf springs, there are really a ton of variables present here so it is hard to predict. However, if you are a full-timer then odds are your trailer is going to be subjected to harder conditions and most likely more weight than the average trailer therefore your suspension components will wear faster. I have attached our leaf spring...
    view full answer...
  • Should I Switch To Heavier Rated Leaf Springs For My Rock Climbing Trailer?
    I recommend staying with the 4-Leaf Double-Eye Spring for 3,500-lb # SP-212275. This will ensure that you do not have to change other parts of your suspension system and the trailer has the correct ride quality. The 4-Leaf Double-Eye Spring for 4,000-lb # SP-051275 may have issues with contacting parts of the frame since the springs are 3/4-7/8" longer. To correct this your spring hangers would need to be moved. The 4-Leaf Double-Eye Spring for 6,000-lb # SP-221275 would cause you...
    view full answer...
  • Comparing SumoSprings Helper Springs And Roadmaster Comfort Ride Shocks For 5th Wheel Trailer
    I would be happy to recommend a suspension enhancement option for your 14000lb GVWR 5th wheel trailer. Starting with the SumoSprings Trailer Helper Springs w/ Line Relocation Bracket # TSS-106-40 which act as shock absorbers taking the brunt of bumps and bouncing on rough roads, and offer 500lbs of support when 50% compressed to prolong the life of your leaf springs and suspension components. This option is great for being maintenance free, but will only fit trails with 3-leaf leaf springs,...
    view full answer...
  • How to Determine What SumoSprings Leaf Spring Enhancement Will Work
    In order to determine the correct SumoSprings Leaf Spring Enhancement System for your trailer, you need to need the weight capacity of the axles and if you have an overslung or underslung axle (which I'll explain). Based on your 2017 Montana's weight, both available kits have the right capacity, so all you need to do is find out if your Montanta has an overslung (springs sit over axle) or underslung axle (springs sit under axle). All this means is the position of the leaf springs...
    view full answer...

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Info for this part was:

Employee Lindsey S
Edited by:
Lindsey S
Employee Jeff D
Installed by:
Jeff D
Employee Randy B
Installed by:
Randy B
Employee Jameson C
Expert Research:
Jameson C
Employee Joshua S
Video Edited:
Joshua S
Employee Chris R
Video Edited:
Chris R
Employee Mary E
Written by:
Mary E
Employee Wilson B
Updated by:
Wilson B
Employee Jessie B
Updated by:
Jessie B
Employee Noah M
Updated by:
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Employee Zach D
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