What's it like for a 91B wheeled vehicle mechanic at Fort Campbell?

You can expect to have all 4 seasons. It will be cold 25-40F in the winter and a muggy upper 80s-low 90s in the summer. As a junior Soldier mechanic you can expect to spend your workdays in the motorpool. It's been many years since active duty, but I imagine there will be weekly maintenance periods (motor stables) where the vehicle operators will do their preventative maintenance (PCMS). Some units rotate their platoons on different days, some do the entire unit on the same day.

You will probably be assigned a vehicle maintenance project under the supervision of your team or squad leader who will work with you as you tear down and do more thorough maintenance on vehicles on a periodic basis.

I don't know what kind of unit you will be assigned to, so I can't begin to guess how much time you will spend in the field. If you support the 101st you could learn to love the field.

Fort Campbell is a nice place Air ASSAULT while tuff in phase 2 is still a vacation from the motorpool. And yes they love to run and ruck.

It really depends on the unit you go to. Expect to go to Air Assault within the first couple months, do a lot of good PRT, and work a good amount. As a 91B you will be working a lot in most places you go. Ft. Campbell is a beautiful place and the people are really friendly, and a lot of unit pride.