[JL8Jeff]

I put 1" lift blocks on the back of my 4Runner since they all sag over time. The blocks came with a hole in the center and the centering bolt. The bolt doesn't go all the way through but the hole does. The centering bolt in the block will position the block in the spring pad correctly and then the centering bolt in the springs will sit in the hole on the block to position it correctly. You should need longer U-bolts to hold the springs to the axle. When you get up to 3" lift blocks or higher, I'm not 100% sure if they use a single centering bolt that goes through the block and springs, but I doubt it.