OK. I took a look at the springs on both trucks, the J10 has a 7 leaf pack, the GW has a 5 leaf pack. I cannot find any definitive answers in the searching I've done. The length should be the same, but I've heard the centering pin is spaced differently. Mostly interested in swapping the rear springs only, but may decide to do the fronts as well. Alot of conflictictions out there, someone set me straight. Here's a link I was looking at for specs., but according to this I don't know if they are correct.