Completely normal...

Using the 4WD modes (4HI, 4LO, 4HI Lock, 4LO Lock) will usually increase noise in the axles, transfer case and the rest of the driveline and is usually greater at higher speeds and will usually increase the more the vehicle is turned. As the vehicle turns, the front and rear axles follow a different arc. When this occurs, the only place to compensate for this binding is between the contact patch of the tires and the ground. This can feel like the vehicle is vibrating, crow hopping or grabbing. Even if the vehicle is driven in a straight line, there are slight differences in tire circumference that will cause some driveline binding. If a vehicle had the exact same size tires and was driven in a perfectly straight line, the fact that more parts are moving would mean that there would be more noise and possibly some feel of the system operating.

 

starts binding very bad

On dry pavement, yes, it will bind very bad because the tires can't slip on that surface. In snow, mud, sand, or gravel, it shouldn't be as noticeable since the tires can slip unless going real slow with no acceleration.

 

you should NOT try this on pavement as it will overstress your drive train. only use 4wd on slippery surfaces