Pitman or Idler arm could be loose. Check it by having someone turn the wheel right and left while you look underneath. If either or both should pop when they go the opposite way of turning, then one or both or bad.
Born and raised in Alaska, and damn proud of it.
1998 F150 Scab, 4.6, 4R70, 8.8 w 3.55ls, XLT. Power strg, windows, locks, drivers seat. 123k troublefree miles. Lund hardshell tonneau and Lear bed shell. 1990 F150 sb 4x4, 5.0, AT Lariat, 88k miles, tonneau and shell. 2nd owner. 98 F150 FS 4x4 reg cab, 5.4.