Used diesel, anyway to tell if it's been chipped?

Not all tunes are done for high output purposes. Some are done for better fuel mileage. I have a Bully Dog tuner on my truck. My turbo went bad and I put in an improved one that wouldn't play nice with the factory tune. It has 4 settings. It sees two of them. No power (basically stock) and towing. I think the others are high and extreme. I like my transmission and rear end. No reason to venture into the higher two.