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When you’re towing a heavy trailer or hauling a full bed of gear, sag and sway can throw off your steering and braking. The SuperSprings Custom Suspension Stabilizer and Sway Control Kit adds 5,000 lbs of rear suspension support by bolting helper leaf springs above your factory springs. As the load increases, rollers on each end automatically engage to lift the rear, prevent bottoming out, and keep your truck level for safer handling.
Crosswinds, passing semis, and uneven corners can make a loaded vehicle feel unsettled. These heavy-duty helper springs act like sway bars, keeping your factory springs from twisting and reducing sway by up to 30 percent. The result is steadier tracking through turns and less rocking when road conditions change or big rigs pass.
Unlike air bag systems that need checking and adjustment, these springs automatically react to your payload. There’s no tubing or air pressure to monitor. When your factory leaf springs flex under load, the SuperSprings engage; when unloaded, they back off for normal ride comfort. That means consistent support without crawling under the truck to make changes.
Every setup is different, so the shackles on this kit give you multiple options. Choose an upper bolt position for maximum load support or increased ride height under constant weight, a lower position to keep the factory ride feel when driving empty, or a mixed setup that balances support and comfort. The dense polyurethane spring pads help keep everything centered and stable through it all.
Installing these helper springs is straightforward—just bolt them above your existing factory leaf springs. There’s no drilling required, and all mounting points line up cleanly. Once installed, the added support not only keeps your suspension level but also helps extend the life of your brakes, tires, and factory components over time.
This kit is designed to fit a vehicle with factory top overload springs. As shown in the picture above, a top overload spring sits above the factory leaf spring pack.
Customer Satisfaction Score:
98% were satisfied with this product
2% of customers were not satisfied
Ratings & Reviews
E-trailer agent James helped find trailer tow package that fit my 2011 Ford Transit Connect and provided appropriate install video. You're a huge help James. The install went smoothly without a hitch (lol).
2013 Toyota Tundra 4x4. Installation went well in my garage with a medium sized C-Clamp. The ride feels that same as stock. Lifted the rear 1.5" which helped off set the 2.5" lift in the front from Fox 2.0 shocks. I have not hauled a load yet.
Product worked as described. Shipping was quick (etrailer used "air" to my state, then on UPS truck)
Easy to install, not sure why they included 2 sets of polyurethane blocks (only one set fit my truck)
Don't notice any ride difference when set at lowest setting. Raised truck approximately 3/4". East to readjust for more preload if needed.
Combined these Super Springs with Timbren load handlers. So far so good.
Great improvement over stock while maintaining ride quality.
Installing these on a 2020 F250 was easier than I thought it would be. I was able to get the springs on whit the center piece and the front shackle bolted without jacking up the truck. I had to jack the frame up a few inches on each side to get the back shackle bolt through. I put the shackle bolts through the bottom holes since I only need the extra support when I tow. I recommend air / power tools for the shackle nuts and it doesn’t hurt using them for the center bracket u bolts. They are lock nuts and they have a long way to run on for each bolt. I did have to bend my parking brake cable hangar out a bit for one of the shackle bolts to clear the cable. The truck seems to sit a little higher in the back. Maybe an inch or so. The ride empty seemed the same except it felt like it didn’t roll quite as much when turning. Rolling over a lip at the end of our driveway the extra stiffness was noticeable, however. I won’t know how well they really work until I get my fifth wheel hooked up.
Couldn’t install on my Class C due to the placement of a propane line from the manufacturer. I was very pleased with the weight and solid construction.
Easy to install and they definately keep my pick up from squatting as much with our trailer hooked up.
This was by far the easiest mod I have made to my 2019 Ford Super Duty King Ranch! Only took 45 minutes start to finish. Didn't even take the wheels off. Took some pressure off of the springs by lifting the rear end a little using the trailer hitch. Used the bottom holes on both ends and only raised the rear of the body 1 inch. Great product!
You should inform customers about special tools needed to preform install. Not on easy install as stated in video
I installed the springs in a little over an hour but have yet to put our 15,500 lb 5th wheel RV on the truck. The pin weight is around 2,800 lbs when she is fully loaded, so we will see if these help us with the sway and porposing, also the side weight when starting into a curve.
No issues with install on a 2023, E350 Class C motorhome.
After chalking the front wheels, I used two 3 ton floor jacks with 13” 6x6 blocks just behind the springs to lift the frame and rear tires off the ground to remove the wheels. For safety, 3 ton jack stands were put under the axles during spring installation
After installing the springs per manufacturer instructions, two 1/2” x 10” pieces of all thread with drilled flat bar were used to compress the front end spring.
With the least amount of preload it raised the back a good inch.
The 800# trailer tongue weight will be the next test to see if more preload is needed for a level ride height.
These leaf springs works great !! More stable my van but I would like that it brings up an inch !!! Great buy
Installed on a 2016 Toyota Tundra. I pull a 28 foot aluminum frame utility trailer. Hauls like a 3/4 ton with super spring. Rides like 1/2 ton without load. I have put 1 ton load on truck with no trailer and the truck drove fine. The front of truck at tires rose 1/2 inch. Installation requires the frame to be lifted off the axel.at rear of vehicle. I like this system better than air shocks as there is no adjustment after installation. I would purchase again.
I have the Yakima EXO Swing Away Storage System w/ 2 Enclosed Cargo Carriers - 2" Hitches on my 2025 Airstream Interstate. They were causing the van to sag. The Springs went on Fairley easy and provided the lift I needed.
Added these to my Mercedes air stream 19x class b van that already has 2 leaf springs. Had swaying issues at 60MPH and up. These put a stop to it right away and kept from sagging in the rear when loaded up with all our gear and water tank full. I have them on the mid setting. My van is 4wd and already lifted so didn’t raise it more than 1/2in. Still has a smooth ride and no big jolts like air bags or sumo springs.
I bought these a year ago so not sure if anything has changed Bad thing is they are slightly too long, Just enough to touch the wheel well and rub the under coating off. If you’re going to install yourself, I found a good you tube install. The U-bolts for install are too short. Need 2 forged C-clamps.
These are a 100% buy, don’t mess with air bags or sumos. These adjust themselves with load or no load.
I bought these as part of my suspension modifications . I had them installed on my Ford F350 SB . I have an Arctic Fox 865 truck camper. It’s a heavy camper so to minimize sag and sway I installed Timbren bump stops, a hellwig bigwig sway bar,Torque lift stable loads. That improved things quite a bit. I installed these super springs last ,they further improved sway and improved the overall stability and ride quality.
I definitely feel these were worth purchasing. I could not decompress the existing leaf springs enough to install these myself so had them professionally installed.
I would recommend them for hauling a truck camper.
Without towing, the truck seems to ride a little smoother. The real test will come when I hook up my fifth wheel. Very simple to install.
This product did exactly what I needed. Lift the RV up to unloaded height. I have not exceeded the 12500 GCWR but the rear end was dragging like it was severely overloaded. It was a very tight fit because the mud flap framing and gas lines were almost in the way. An entire day later with a couple of clamps and sore wrists at max setting fixed the sag perfectly! I wish I had before and after pictures. I can almost fit my head in the wheel where I could not get my arm in before.
Fast delivery, free shipping, the springs went on pretty easy, had some problems with install due to my vehicles configuration, Travato59K,not the springs. This was a 2024 RAM Promaster3500, raised it up 1.75” on the lower setting. Noticeable help with sway problem.
The shackles on each end were too narrow to clear the spring clips so locating them was harder than need be. The instructions had a mistake, locating the front shackle incorrectly. Installed as they are. Improved ride a lot. Glad I got them.
Exactly what I needed and what I wanted very fast shipping thanks E trailer
While use the middle setting it only gave it a slight lift with a minimal unloaded bounce. Usually never overload the trucks maximum capacity but needed to for a short distance and with approximately 1300 pounds in the bed, the truck didn't squat at all.
This was a great addition to the suspension of my 2021 Ford E350 Class C RV. The rear springs were at almost max load. This raised the chassis at the rear axle almost 2-inches. This is a heavy duty spring and I had to fabricate a tool to compress the spring.
Fit great on my 2025 Ram. I makes a big difference pull my 14000lb 5th wheel. Highly recommend these for any heavy loads. I have put these on 3 other trucks and they are maintenance free. You don't need to worry about the load you are hauling.
Running a 2017 chev 4500 cutaway box truck for my business. Truck weighs in around 12,500 lbs. Added these to help out with sway and load management. After install has been an awesome addition! Raised my wheel well about 2". Has performed great!!
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