2005 Chevrolet Avalanche Tire Issue

The difference between P and LT means that the P means passenger and LT means light truck. I don't think the tires would do it but I suspect from your description the truck is lifted and that will because the front end geometry is screwed up. If you lift the truck then you need to put the correct stuff along with it to straighten the geometry. As iv'e never had time to mess with tires so much you might ask a tire store if the LT tires have stiffer sidewalls as that is usually the case between p and LT tires. The P tires will give a softer ride due to less air pressure in them. But just tires won't wear your front end out part wise, also cheaper parts will as well.