Lately, the steering wheel would not return quickly to its straight position after completing a turn. What could be the problem?
No, it is the ball joint to the pitman arm. Please see the picture. The idler arm has been replaced two years ago by the previous owner (the dealer).Yah, and the nut is friction fit. Regardless how many spacers you have or had, any that fell out will leave a gap, - along with giving you a clunk when you turn or hit a bump.
And, I think you're referring to the idler arm. If you can't get grease in it after replacing the zirk then replace the arm. If it wobbles at all then replace it. If it's over 3 years old then replace it.