Welcome to the forum Ethan! Assuming you have coil springs (leaf springs were an option) you should not need lowering blocks, just the coil lowering springs. Check out my build thread link below. I changed my rear coils twice. The standard lowering springs were horribly weak and about the only thing you could haul in the truck was a cooler! Second set were heavy duty 4" lowering springs. Same ride height, much better load capacity. Good luck with your project. John