So as I'm shifting through gears today in my S4 suddenly the shiftier became stuck in first gear. As I freed it from the first gear shifting became like shifting trough frozen peanut butter with chunks of peanuts in the way.
Here is the aftermath:






Notice the chunks got caught up in the grease (not peanuts).
Looking down in the transmission it looks like there is a plastic ring that broke into pieces. Is this a common problem, is it an easy fix?

 

yes its common and an easy fix.

 

although that normally just makes for a sloppy shifter.

 

Haha yea that supper easy to fix. It's a 20+ year old brittle plastic bushing that is relatively cheap to replace. There are two plastic parts. One goes over the ball and one goes under. Check out mazdatrix for the parts.

 

That's a bunch of broken bits of shifter bushing. Mazdatrix sells the shifter bushing kits... actually a lot of places sell them. There's probably nothing wrong with your transmission. On top of that, the picture you've taken is of the extension housing, not the inside of the transmission. Go under the car and there's a plate on the passenger's side, right on the side of the extension housing where the shifter is. Take that plate off (4x 10mm bolts) and clean all the chunks of plastic out (from both the top and that side cover). Replace the cover and go up top, pour some gear oil in the extension housing and replace the bushings. It's a super easy fix.

 

I did replace the oil in the transmission 5 months ago. I don't recall pouring any oil into the extension housing, how much does it need?

 

Boy I'm glad I decided to replace my entire shifting setup before that happened lol. At least it's not the actual trans itself man. +1 on the Mazdatrix bushing, it's what I use.

 

I can't remember. It's in the FSM.

 

I've recently replaced my 1988 transmission with a transmission1990,
the shifter i'm using is from 1985 rx7. Would that be a problem, using a 1985 shifter in a 1990 transmission? I'm trying to figure out weather that caused the bushing to fail.

 

The bushings are brittle plastic that are really old. Like...from 1985. Things wear out with time and use. Clean the junk out, replace the parts, and change the gear oil.