1990 Ford Ranger Tranny problem?
 

I new here so hello..Heres my question, this morning when I was driving my truck to work (1990 Ford Ranger 4cyl Reg cab 2wd Auto) I had it in Drive until I got off the dirt road until I get on the main road where I put it in Overdrive. When I went to put it in Overdrive I noticed the speedometer and the odometer was not working at all. I then noticed the overdrive wasn't kicking in like it was still in drive. I let off the gas and the engine torque does not slow the truck down anymore like it did before its like it goes into neutral when i let off the gas. Any Ideas?