It's that time of the year again where it's snowing and I'm going to take the Jeep out. The only problem is when I shift into 4hi and start to drive the jeep starts to jerk until I get up to about 10mph. The jerking is especially bad when slowing down to make a turn and then accelerating. After I hit about 10-15mph it stops. This can't be normal. Any ideas? 2004 4.0