4 wheel drive noise
 

When driving in four wheel drive at low speeds (below 15 mph), there is a squealing coming from the front end of my 1998 24 valve dodge cummins. This noise almost sounds like a fan belt, but it is not present at idle or at speeds above 15 mph. It is present in both four low and four high on both snow and ice. This noise does not occur in 2 wheel drive. Anybody have any ideas as to what the noise could be?

Time to check the U joints on the wheels and drive shafts along with the front bearings. 4WD puts more stress on them so if they're goin bad that will be when you notice it the most.