I'd long gotten used to the sound of my ole 7.3, so was surprised when I fired her up to leave a campground a couple of years ago and some woman walking by held her hands onto her ears as I drove off. Wished I would've had a matching train horn installed at the time for her dissin' my truck.
The 7.3 is most noticeable accelerating in town and at high rpms while climbing grades. On the highway in overdrive, the ole gal settles down at some 1500 rpms or so with its 3.55 axle, so the other highway noises overcome the distinctive sounds of the diesel, relatively speaking of course.
But I forgive all of its clattering when I figure my fuel mileage, which is in the fourteens towing and the twenty-ones not towing while on the highway.