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 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, the rubber spring will be in contact with the vehicle’s frame. This contact won’t affect ride quality — you’ll still enjoy a comfortable unloaded ride, too.What makes Timbren SES kits different from other suspension enhancement systems? Unlike air bags, our kits require no post-installation maintenance. And unlike other systems, you can install and haul in under 30 minutes, right from your driveway.