My 99 has transfer with 4wd low, part-time, & full-time. Over the years I have felt the full time was great for driven in snow. Last month I had tie rods replaced & new abs sensors installed. Since then the front end fees much tighter. Not jerky, but responds fast.

During christmas we had a small snow. As usual I put it in 4wd full time. The truck was really jerky at low speeds (15-25 mph). At higher speeds (35+), it was better, but would still jerky & pull from side to side. Almost like front wheels was engaging & disengaging. Not the normal feel.

I use my 4wd 2-3 2mes a week from fall to spring for work & often us it while hunting. It has never felt this way, could something be wrong with hubs that would cause this feeling on fresh powder covered snow roads. Part time maybe, but full time has never done this.

 

The front hubs don't engage/disengage on our trucks. They are always connected, it's the transfer case that engages/disengages the front drivetrain. While you're moving, no matter what position the t-case is in, the entire front drivetrain rotates.

Start out with a thorough check of the CV joints, the front propeller shaft, front differential, even the transfer case - yours has a built in differential to split the power.

It could possibly be a shifter adjustment, maybe it's not fully engaging in full-time.

 

could be your alignment is slightly off too.