I have about 26K miles and need new tires on my 2002 3500. (Sure doesn't seem like very good mileage on BFG tires that came on the truck when new. What is typical?) All info in manual and I have read on these sites says not good to change tire size because it will mess with Alli shift points, etc, etc. I have LT215/85R16 tires now and they look kind of small on this big truck so I would like to go bigger but just curious about what people who have increased tire size anyway have experienced. Don't want to do anything to effect performance towing my boat and hauling a truck camper for the sake of looks and I don't want to race.