Unstable loads while towing and hauling don’t just make for an uncomfortable ride. Difficult handling, rear sag, and corner sway create dangerous driving conditions — for you, your passengers, and other vehicles. Whether you’re towing your RV across the country or hauling hay down the highway, our Timbren SES kits are the best solution for upgrading your Chevy Silverado or GMC Sierra suspension. These kits level your load, making for a safe, controlled ride so smooth, you might forget you’re towing altogether. How? Our Aeon® rubber springs deliver a progressive spring rate. As load increases, our rubber springs push back harder, eliminating squat, sway, and roll . After installation, there should be a ½” to 1 ½” gap between the rubber spring and vehicle’s frame — meaning you’ll enjoy a comfortable unloaded ride , too. What makes Timbren SES kits different from other suspension enhancement systems? Unlike air bags, our kits require zero post-installation maintenance . And unlike other systems, you can install and haul in under 30 minutes , right from your driveway.