Last night (the 1st) I changed the oil (M1 10W30) and the rear diff fluid (Redline 75W90).

Whee! Rear diff required a syringe. Not sure what I’m gonna do about the gearbox.

I flushed the power steering fluid in the Miata today. After checking miata.net I found the reservoir and replaced what was in there with Mobil 1 ATF, which is apparently Dexron II compatible. I did a siphon/replace, then drove around for a bit, then siphon/replace, then drove around a little bit, then siphon/replace again and a small test drive. The steering feels a wee bit weightier now, which is a good thing I think. We’ll see if this cures the “power steering feels really gummy for the first minute or two” issues I’ve been having.

In other news, the 90K maintenance is overdue. What’s involved, you ask?

http://www.miata.net/garage/maint.html

• Replace engine oil and filter;
  
• inspect drive belts;
  
• replace air cleaner element;
  
• replace spark plugs;
  
• inspect idle speed adjustment;
  
• inspect fuel lines;
  
• inspect cooling system and replace coolant;
  
• inspect brake lines, hoses and connections;
  
• inspect brakes and pads;
  
• inspect steering operation and linkages;
  
• inspect front suspension ball joints;
  
• replace transmission oil;
  
• replace rear axle (differential) oil;
  
• tighten bolts and nuts on chassis and body;
  
• inspect exhaust system heat shield;
  
• lubricate locks and hinges.

So I guess my shopping list is:

• air filter
• coolant…?
• transmission fluid (mt90: http://forum.miata.net/vb/showthread.php?t=213617&highlight=mt-90+mtl)
• diff fluid (75w90)

Not bad, just have to get around to it.