Well I've been talking up the SDL. Now my Brake Tensioner is going bad for like the 3rd time in about a month. Does anyone understand why that is? I had it replaced because it needed it, then after about 10 days I noticed that it was making a "vibration" noise, especially at idle. You could actually see it moving up and down a tad. Got it replaced because the MB shop said it was defective. Now here it is about 14 days later and i'm seeing it again. Does this sound like another defective Belt Tensioner or is there some other underlying problem that could cause this?