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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
Brooke M.
6/5/2025
Hey, Cail! Glad to hear that these helped to level everything out. Where are you traveling to?
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.
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Trevor T.
10/17/2022
Ive kept them installed for the last year and the cars ride quality has never suffered. Great product!!