Hi, I'm asking for advice on my Rx-7 I recently purchased. I can shift up just fine however as I approach a red light going around 25 mph in third, I press in the clutch and attempt to shift into a lower gear (with the clutch still pressed in) and the shifter physically does not allow me to shift down into either second or first until I am going around 5 mph or less. Intrigued by this, I take to the highway and shift up to fifth gear, then take an exit and begin to slowly stop. Again, with the clutch pressed in, I attempt to shift into the following gears with the following results:

Fourth, Second, and First: Physically cannot until vehicle is going around 5 mph or less.
Third: Can downshift into third, however while doing so, some grinding can be heard.

What could possibly be the culprit here?

 

In my meager knowledge of actual transmissions, I would guess its the syncros.

 

From the large amounts of research I have done, it most likely is the synchros. Can I buy new synchros online or should I hit up a junk yard for a donor transmission?

 

donor would be easiest unless you have experience with rebuilding transmissions

 

If its an n/a find a donor..they are cheaper then cheap.

If its turbo then its your call.