To provide increased safety and comfort for 2011-2015 Chevy/GMC C/K 3500 commercial trucks when towing or hauling heavy loads, Air Lift Company offers the LoadLifter 5000 ULTIMATE (88339) air spring kit. These fully adjustable air springs help reduce driver fatigue by improving the ride characteristics of a fully loaded vehicle, working with the existing suspension to deliver up to 5,000 pounds of load-leveling capacity and improved handling.