Want new vehicle is true real 4 wheel drive 4WD

Part TIme = not for use on surfaces with good traction. 4WD = both axles driven. Since the part time 4WD has no provision for slippage (like a differential), they are not for use where at least one wheel cannot slip to relieve off balance stresses in the two axles. Once you get to the axle, the behavior is determined by the differential - same as the drive axle problem with 2WD. Trust me, for snow and "normal" circumstances you don't really want what you appear to think 4WD means (power goes to any one wheel with traction). I had that to some degree years ago in an old Scout with limit slip diferentials on both axles. One good snow storm convinced me that it was inherently dangerous and the front ls came out real quick. Locking-limited slip differentials on both axles has it's place and is useful in specific situations but on ice-snow - or even Texas clay mud - fully locked is a tricky proposition. It also tends to be hard on the running gear - any one axle shaft has to be able to handle the full torque of the engine.

There are tricks to help the situation you describe - applying the parking brake, tapping the brake pedal, etc. Some are covered in the owner's manual.

-- Will Honea