I would say warped rotors with a lot of certainty.
2002 Jeep Grand Cherokee Limited 4.7 low output quadradrive. 31in General Grabber AT2, OME HD, bilstein 5100, IRO sway links, addco rear sway. Kolak 3in exhaust with flowmaster SUV 50, magnaflow 3in cat, Custom K and N FIPK, modded airbox with ram air, Fastman 71mm Throttle body, PML RFE Deep pan, Autometer digital trans temp gauge, P.I.E. aux adapter, Infinity reference 3.5/6x9/6.5, 200w inverter, surco rack, front/rear/cargo husky liners.