I don't know anything about axles and wheel bases. I have a 2518 and I tow with a Chevy Astro. They have a 5500 lb towing capacity. Most mini vans are 3500. We towed it home with a Nissan Quest and no wdh. It was a harrowing experience. We had no idea that it would be that heavy. The Astro, however has been great and the wdh was a must. When we replace the astro, we will go to a full size van to make more room for our dogs (who's numbers may be increasing soon.) Next I will start working on DH to get a bigger TM.
Cheri