I had the same question as you, and I think the 14,000 towing limit is the amount which the truck will safely tow, i.e., navigate through traffic, hills, which involves stopping, turning, accelerating to highway speeds, etc. I think "pulls," on the other hand, is the amount which the truck can pull behind it, albeit slowly and not in traffic conditions. Towing means able to transport and navigate through traffic, "pulls" is just budging it from one place to another.