I was running at full throtle when I heard a loud whining noise coming from the motor. I immediately shut down the motor. I then restarted the motor and tried to shift and nothing, no forward or reverse it didnt even sound like it was trying to engage. I'm sure I didnt hit anything and the lower unit oil was clean, no water or shavings. I was told by the repair shop that they think it may be a sheared drive shaft that the 90's and 115's were notorious for broken driveshafts. I was hoping someone hear may have some insight.