Ford Repair Questions? Ask a Mechanic for Answers ASAP
Hello, do you have a way to scan for codes?
Having to rev up the engine to engage reverse indicates there is a leak inside the transmission. By revving the engine you are increases transmission line pressure to engage the trans. It's possible the transmission can be going out and is causing your clunking noises as well.
If you have the vehicle idling in park rock the steering from side to side. Does it make a clunking noise?
It sounds like your concern is going to be internally inside the transmission.