I was swaping out a failed starter on my 4x4 1992 suburban and there is a sensor that is close to the starter... the starter came out and swung over and broke this sensor. I can't remember if it was in the engine block or the transmission...from under the truck looking up at the starter (my view for the last couple days) it is sort of up and to the left of the starter. I can say now that the truck is running it will not shift. I'm not sure that has something to do with that sensor, or when I dropped the steering column to replace the ignition switch and I messed something up on that end... It worked fine a couple weeks ago before the truck wouldn't start.