My 2002 300M will not go into any gear fwd or reverse. I was travleing at about 70mph when their was a lound noise and then the RPM's shot up to 3200rpms at 50mph. Once i came to a stop the car would not go back into gear until i manual put it in 2 gear. Ireceived 3 codes. Gear 1,2 and 3 out of ratio. Is it time for a new tranny?

 

Sounds like you could be in for a major rebuild....were there any symptoms of trouble before this happended?

Maybe its just an input sensor...thats a $15 part

 

I would go with the sensors first