Seeing as how last night I finally did oil and transmission fluid, thought it would be nice to share some info on how to change the MX-3 transmission fluid (PITA without any previous info).

Required:

• 3L of 75W90 gear oil (Redline is my preferred brand)
• Fluid transfer pump ($10 from Partsource/Walmart/Canadian Tire)
• 23mm socket

Instructions:

• Run the car for about 2km. Let it cool for about 15 minutes. Jack the car up safely.
  
• The transmission is located on drivers side of the engine bay. Above the plastic shield is a 23mm bolt, loosen it. It is facing towards the front of the car, and is above a sensor with green wires. This is the fill port.
  
• On the bottom of the transmission is a 23mm bolt. This is the drain port. Remove it and remove the fill bolt.
  
• When all of the fluid has been drained, replace the drain bolt.
  
• Insert one tube of your fluid transfer pump into the fill port, and the other end into your transmission fluid. Pump 3L of transmission fluid in, and replace the fill bolt.
  
• Lower the car, and shift through the gears (WHILE THE CAR IS OFF).

Congratulations, you've changed the transmission fluid. It fixed my issue (jerkiness in 1st/2nd). Make sure to read what fluid you need for your MX-3. I'll be uploading pictures and the factory recommendations.

Good write up however,,,you didn't mention where the fill bolt is located maybe mention to dispose of the old oil in an environmentally responsibly manner.

Hey can you show me a picture of were the vent is on the G5M-R.

Don't mean to clutter but I thought the fill port was the speedo gear hole?

i was gonna mention that too and i think that's just for 4cyl's