I've got a set of machined down factory blocks and matching U-bolts that will level a 2nd Gen 4x4 with the 3" wide rear springs. If your trailer is hard to back under because your truck is too high these can help alleviate that. They may also keep you from having to flip your trailer axles. Or they make your truck look really good with the level look and don't require that you lift the front which can cause excess wear and tear on the front end. They are for sale in the classifieds but I'll now take $50. 00 for them.