2003 Isuzu Rodeo 4x4 3.2L V6 Auto motor noise

2003 Isuzu Rodeo. 3.2 V6, 4x4, towing package, power widows, power locks, tilt wheel, cruise, 6-disc factory CD, A/C, running boards, roof rack, NEW brakes - front and rear. 115,800 miles - 2nd owner. It starts up and drives but has a very loud click. Body and everything else in GREAT SHAPE!