When I take off in first gear the car shakes really bad. When I made my last pass at the track last year I stoped and got my time slip. When I took back off I could not hardly get it back in gear. I let it set and cool down and it wasn't as bad. It just shakes bad now it's not slipping like it was when I had it replaced the first time. I can smell the clutch when I was making a pass. This is my dd and the clutch has about 40k is it time to replace it or could it be something else.