yeah , I did a search regarding this problem . a couple people had it previously and fixed it by replacing trans . Never really found out what the cause was . so maybe someone has an idea??

reverse will NOT go in not with the car turned off , not with the car on nothing it is locked

I know 5th and reverse share a synchro and my 5th was grinding , aslong as I double clutched I could get it in without a grind ..


So I'm wondering if anyone has any idea what could it be ? or is it more then likely time for a trans rebuild / replace .

 

Hade this happen to me but i was Completely locked out of reverse even bent my shifter trying to get it to go in could not figer it out I replaced the Trans clutch and pp I know one guy had the Trans locked in reverse and he was able to get it undone with the help of a trick found on the miata forums might help but imp its time for a new rebuilt Trans or a low mileage one

 

You probably have a piece of synchro broken off and getting lodged in there. Sounds like its time to pull the trans.

 

already done . Getting it rebuilt TY for the responses guys , and yeah i'm guessing its something like that .