I bought my trailblazer back in September with 18k on it. It shifts HARD. I previously had a 98 TA with a tune and honestly they shift almost the same. I have read that an untouched trailblazer should have a smooth shift, is this true? This may be a silly question but is there any way to tell if it has a tune? I bought it from a dealer that didn't know jack about it. Or is there other things I should look for? Any input would be awesome!