I have an 03 with the 8.1 and the ali. Pulled a trailer into and out of the mountains of Co and the oil in my alli turned dark and smelled like it might be burning. Took it in and the dealership check pressure and said they were all right. Dropped the pan and said it had a slimmy black stuff in the bottom of it. They took an oil sample and changed the oil and filter. Lost the oil sample in the mail. Truck now has 9,000 miles on it and the oil is turning again. Anyone else have anything like this or any ideas?