Anyone changed their rear end for more towing capacity?

You can change gears and it will make a difference. The other question or questions you need to consider concern your total weight. If the TT has a 7500# limit what will it weigh when you load it with all of your gear etc. How much do you put in the TV, people, firewood etc. I don't know the towing specs on your TV but take a minute and look at the total unit truck and trailer and examine if you have enough truck to handle the load. Good luck.