I don't think it's related to the cold, but the fact that extreme cold seems to make sounds and/or noises more prominent. And sorry, I meant upper control arm bushings or lower control arm balljoint. My mind's all over the place and I've been thinking faster than I can type. LOL. With regards to the upper control arm bushing sleeves, are they installed dead center or would it not matter that much? The reason I'm asking is when I looked at both rear uppers, the driver's side bushings were centered, but the passenger's side are off center.