My T14 bit the dust today...

As I was going to work today, I down shifted to 2nd as I was making a left hand turn and my T14 tranny started making a very audible clicking sound plus I could feel a vibration in the shifter and the floor. The clicking sound / vibration gets louder and faster as speed increases. It does it in 1st, 2nd and reverse but not in 3rd. The transmission has not been giving any problems other than a slight oil leak. I wonder what happened to it, but I'm not going to repair it. I have a T176 four speed, a D300 tcase and a centered D44 rear that I'm going to swap in (sooner than I thought )