Heading up to Sinclair Ford this am about 7:15 to install new fuel gauge. Clear day with temperature 20 degrees, high humidity on to I-55 north into passing lane in 3rd gear. I've done this hundreds of times. Never when it was this cold with my GT. Frost on highway. Started to spin, couldn't keep up with it and slammed a guardrail about 60 MPH or so. Damaged every surface of GT. Probably totaled. No damage to me other than a crushed ego.