You were supposed to title your vehicle in Texas within twenty days of moving to that state. If you try to transfer the New Jersey title, it may work but I can't promise that your buyer won't have difficulty trying to register the vehicle. Texas will charge sales tax when the buyer transfers the title, based upon the sales price (or, if that's unreasonably low, book value). You must file a vehicle transfer notification documenting the sale. It appears that you can transfer license plates to another vehicle you own by obtaining a corrected vehicle registration form from your county tax office.