Has it been alligned since the suspension work? If yo did he control arm bushings it should have had an alignment. Also, what kind of tires did you put on it? I'm from Canada, and I can tell you, if you have your typical perfomance tire from michelin which are very hard rubber, these cars won't go anywhere in winter. I had someone who wanted to sell the car they were so frustrated, I switched the tires to a set of goodyear winter tires, and the car now handles like a dream in even the worst winter conditions.