1999 won't go into 5th/reverse /:
 

just picked up a 1999 anniversary addition with 93k miles for 3.6k!!!! Crazy right? Anyway after the test drive and all it woul not go into 5th gear as much as I tried and then it wouldn't go into reverse. I can't find any information exactly as to why but it was doing it just find for the test drive and driving it home for a couple hours. Any ideas? Rebuild? Selector pin? Thanks for replies

Go check out the garage section at Miata.net.

I believe the guy above me is referring to this: https://www.miata.net/garage/stuckreverse.html

I've never had any experience with that issue but article suggests this is more common in early NA's than NB's. May be a good place for you to start, though.

ive read it could be a nut connected to a wire I need to move but it's not stuck in reverse it just will not go into them! The car drive good otherwise. The shifter moves a lot and needs a rebuild but I'm not sure if it's only a rebuild that will fix it or a slide selector l. Guess I seem to be the only one with this problem :(

fix the bent/broken shift fork in your transmission

Or buy another 5 speed. They're like 100 bucks these days.

10th AE should have a 6 speed.

Oy... I just noticed that mine has been a bit cranky getting into reverse lately too. It protests a bit, but it's totally fine if I get into gear and move a bit before trying again. I'm hoping that rebuilding the shifter and/or changing to the ford unicorn tears transmission fluid will make it a bit happier!

https://www.miataturbo.net/suspensio...6-speed-41149/

My 6 speed had a crunchy 3rd gear and reverse was difficult to engage. I replaced the oil with Redline MT90 and the forward gears shift lovely when it's warm now. 3rd is still a bit crunchy when cold, but it's buttery smooth on track. I still have problems engaging reverse. It's never as easy as just pushing the clutch in and selecting R. It never wants to engage, so I put it back in N and let the clutch out, depress the clutch, and then it will go into R.

I may try out the magical Ford full synthetic XT-M5-QS manual trans oil, when I replace the fluids at the end of the season. It's $24/qt: