I assume you plan on hauling the shredder sideways and disconnected from the tractor?
Is that really necessary? We are allowed 14' for implents of husbandry IIRC in PA.
I currently have a F150 but will be upgrading to a 3/4 ton or maybe a 1 ton. I have a good lead on a nice deck over trailer. It is a bit overkill but I think for the money it is the better option. It is a three axle goose neck trailer that is 30' long and tilts. The wheels need to be replaced and bearings need to be looked over, but the trailer can be purchased for 2500.00 cash.
Check the laws in your state. A three axle trailer likely has a GVWR of 21,000 lb. Coupled with any truck that puts you over 26k. Most likely will not need a CDL just hauling your tractor around but you may very well need a Class A non commercial license.