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When towing or hauling, a sagging rear end can throw off your braking, steering, and headlight aim. The RoadActive Suspension Custom Leaf Spring Enhancement Kit – Heavy Duty adds up to 3,000 lbs of load support by converting your factory leaf springs into a mechanically active suspension system. Variable-rated tension springs automatically adjust to the weight you’re carrying to keep your ride level and stable whether the bed is loaded or empty.
Heavy trailers and top-heavy loads can cause sway and body roll that make long drives feel sketchy. This RAS kit strengthens your existing leaf springs to prevent that side-to-side movement before it even starts. It also absorbs torque to eliminate axle wrap and wheel hop so your tires stay planted through curves and over bumps. The result is better traction while braking or accelerating and steadier control when hauling or towing.
Most helpers stiffen the ride when you don’t need them, but these tension springs disengage when unloaded so your truck rides normally. Once weight hits the bed or hitch, they immediately activate to take on the strain. That means no harshness when driving empty and no bottoming out when loaded—just a balanced ride that feels right all the time.
The fully assembled RAS units bolt directly under your leaf springs using the factory U-bolts, with no drilling, cutting, or welding required. Each coil spring can be preset during install for 25% to 40% tension using the included spacers to match your needs or level off an uneven load. Once installed, no air lines or adjustments are needed—just reliable, maintenance-free support every time you head out with a trailer or heavy gear.
Each component is built from high-grade alloy steel with an epoxy e-coat for corrosion resistance. End brackets have been tested to over 800 hours of salt spray exposure so they can handle years of road grime and weather without breaking a sweat. This durable design helps extend the life of your leaf springs, shocks, shackles, and tires while keeping your suspension ready for whatever you haul next.
Customer Satisfaction Score:
95% were satisfied with this product
5% of customers were not satisfied
Ratings & Reviews
Gwendolyn Y.
12/17/2024
Hey Nathan, let me know how to tow goes and how you like the handling.
Tony
4/20/2022
This a great product, it truly helps the suspension of my truck, both with or without a load..works great!
Dave
2/10/2022
When originally installed, I adjusted these to the highest setting. That was more than I really needed. Backed it down to the lower setting. I get all the ride height control I need along with a better ride. Body roll, axle wrap and all the other unsettling gyrations are eliminated. Buy these, put em on and forget em.
Anthony
4/15/2023
Great, the RAS has worked just as they describe. A more stable ride while pulling the camper, smoother while hauling a payload. Very pleased with the product
Tim
4/7/2023
Still working wonderfully. No sag, rear sticks to the road when cornering, can hardly tell when youve got a load or are towing a trailer. Even pulled my buddys 28 Cougar trailer with no issues. Excellent product, and love the adjustments.
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Jennifer
4/1/2026
Towing is still so much better and the look after my tundra is amazing.