I75 from Knoxville, TN to Lexington KY

We went that route probably 15+yrs. ago and going south but from the Ky./Tenn border it's a beautiful drive. Some fairly steep grades for this flatlander but easily manageable in a gas MH w/toad then.

Enjoy
Dave

As others have said, no problem. There is only one hill NB that you may slow down a bit, but in our E450 c-class with toad, whe are able to maintain 50mph.
If you have engine/transmission braking 'tow haul mode' use it and you probably won't have to use your brakes.

Beverley & Ken

Just before the Kentucky border there's 4 miles of 4-5% grade, that's as bad as it gets.

only "mild climb" is Jelico mountain and its not that bad at all. As mentioned there are several grades along the way, once north of Berea KY its fairly flat.

You'll run into some grades, but nothing bad. I was pulling my 35 footer through there for the first time, and was a bit concerned, but had no problems. I just wouldn't do it in snow or ice, or in high winds, but other than that, it's not bad at all.
Also, whenever you're beginning to go up a grade, you will usually find an additional slow lane for RV's and semi's.

You will have no problem on that route.