SVL Inner Gear Kits and Diff Cases. Engineered for Performance. Backed by Dana. SVL parts offer all-makes coverage, as well as the durability and performance you would expect from Dana. The combination of SVL inner gear kits and differential cases provide you with everything you need for a complete rebuild. Get all the parts you need to avoid premature failure in your differential case, and enjoy all of the features and benefits that SVL drivetrain products have to offer.