I recommend covering your tracks too. I have a KK 84" that I use on my DX55. That's about a foot wider than my tracks. I think I probably have around 45 HP out back. I have heavy, hard, compacted soil, but I have never come close to lugging the tractor. On untilled ground, the limiting factor is the weight of the tiller and the depth it can cut on a first pass. A hydro tractor could go slower than my geared one, so that would help. After that, I can bury the tiller but it does not work the tractor at all. In fact, I could till in mid to low RPMs but the tine speed is too slow so I bump up the RPMs. As a comparison, a 2 bottom plow gives this tractor all it can handle in the same soil.