I'm assuming you mean the front axle correct, and your truck is 4x4 right?
If so, you have a Dana 35 front axle, but they came with auto locking hubs. If you have manual hubs, then someone more than likely put those on at a later date
Some came with manuals from the factory. They are WARN hubs, but I believe they just say 4x4 on the knob. If your truck has a 4.0, then it has the 28 spline 8.8 rear w/ 10" drums and Trac-Lok L/S and up front you have the true D35 (open).