Yup. Unless shocks are changed to compensate for them being gone, your gunna need them to keep the front end from giving a "floating" feeling. Some dont mind it or actually like it so its a personal preference
I noticed mine looked like that a while back, and I took them off. I haven't put anything back on yet, and I have noticed the "floaty" ride. What is the part number for the yellow ones?
I just checked GM Parts Direct, and they were about $16 a piece. After shipping, you would be looking at about $42 total for both. I'm sure Henry could get you a good price too.
I bought mine form the local dealer $60.14 for the pair out the door. I'm ok with it truck rides better, not sure why but it feels better over the bumps.