[Prematuregrey]

At some point mine was swapped to the 14 bolt as bigdav suggested. Its got the 3.73's in it with a BBC/th400 and they are a good highway gear for it. Without a tach, I'd say I'm sub 2k RPM's cruising the highway at 70 with roughly 33-35" tires. That is what I'd recommend doing as long as your not planning any heavy hauling. Mine could use a little more umph when dragging my Toy (about 8,000lbs trailer and all) around on the steep hills but it gets the job done as well as any other truck I've hauled the same load with. I'm looking to switch it back to the 4.11's and then shooting for a winning lotto for a GV overdrive setup. I definitely wouldn't go any lower than 3.73's for a 4x4.