Brake Light came on and strange noise form transmission
 

Started my 69 C10 with a 700r4 up yesterday and the brake light on dash lit up. Never happened before. Drove about 100 yards to put it in garage. Stopped short of the garage and attempted to put truck in park. There was the sound of gear teeth clashing. Immediately turned engine off. .
Put truck in park and restarted. No lit up brake light and felt normal driving into the garage. Put it in park in garage with engine running and no clashing of gears.
Any ideas as to what is going on?

Re: Brake Light came on and strange noise form transmission
 

It sounds like you have an electrical gremlin that is trying to lock up the convertor. Which is also shorting the brake light circuit.