As far as the transfer case shifter, i'm not sure either. I have a 97 and i haven't had to replace my clutch yet. I'll find out on our jeep website. What kind of tires does he have? I have 33's and they are bias ply and i always have a rumble in the steering wheel. When they were first balanced and put on i had a bad vibration, so i rotated the fronts to the back and it got much better. Bad balance job i guess. Maybe the steering stabilizer is shot.