I installed some manual locking hubs, mile markers. I drove about 15 miles and went to inspect the hubs and found that they were really warm, hot to the touch. Is this normal with manual locking hubs? I have them in the off position. Anyone experience this before?

 

No, are the bearings too tight?

 

x2 on the bearings. If the hubs are free, and your brakes aren't dragging they should be cold.