Freshening up the gearbox
The Miata already has relatively fresh Mobil1 5W-30 Full Synthetic motor oil and no records were available on the last time the transmission fluid was changed so I decided to get that done today. After reading lots of praise about the Motorcraft XT-M5-QS Full Synthetic Transmission Fluid I decided to give that a go.
Two quarts of the XT-M5-QS ran $38.41 at the local Ford dealership, and I also picked up a Gallon Hand Pump from Autozone ($4.38) since the fill location on the tranny makes it difficult to pour the fluid in. While I was there I also picked up a Haynes manual for the car at $23.53 (I’ve had one for every car I’ve ever owned and they’re pretty handy…)
2 quarts of XT-M5-QS and a hand pump to fill the transmission
The manual suggests that the car is jacked up level (all 4 corners) but I’ve only got 2 jackstands handy right now so I just improvised a bit. After getting the car up on the jacks I removed the fill plug and the drain plug for the transmission, and let the old fluid drain out into a oil drain pan.
Car on 2 jacks only...
Fill plug removed
Drain plug removed
Since I only had 2 jackstands the car was lowered to level to let the remaining fluid drain out, and then jacked back up again. Inspection of the removed drain plug shows metallic particles in the oil. As the drain plug is magnetic most of the particles should stick to it, and the oil + particle mixture had the consistency of metallic paint
Transmission fluid drain plug buildup.
Giving the plug a quick clean reveals the magnet:
Clean(er) drain plug with the magnet in the middle
Now the drain plug can be reinstalled on the car, and we can begin pumping the fluid into the trans. I had to modify the pump a bit since a Gallon Pump wouldn’t fit over a quart bottle (no surprise there), simply by cutting the provided clear tube to have one end reach into the bottle and the other into the fill hole.
Modified a bit to have the tube reach into the bottle
Now with the drain plug back in and the modified pump the transmission is filled back up with all of the 2 quarts of the XT-M5-QS. After this is done the only thing left is to replace the fill plug, tighten and lower the car…
Pumping the new trans fluid into the transmission
Fill plug back in place and ready to be tightened
I filled up the used trans fluid into the empty Motorcraft bottles to see how much transmission fluid was actually removed from the car out of curiousity. It was roughly 1.7quarts, a bit low considering Mazda recommends 2 liters (2.1 quarts). First drive impressions is that there is definitely no longer a faint whirring noise coming from the tranny, though shifts are a bit less smooth for now. Lots of people say that it takes a while for the fluid to work into the gears so I’ll keep track of how the shifting feels in the meantime…
June 5th, 2009 at 18:22
Doesn’t even look like you busted a knuckle!
June 5th, 2009 at 22:07
No busted knuckle.. The wrench did slip when tightening the fill plug and I have a small cut on the ring finger. That transmission fluid + metal particulate mixture on the drain plug was a pain in the ass to wash off the hands though.
June 7th, 2009 at 07:54
What made a HUGE difference in mine was replacing the shifter turret oil! Simple and cheap and can make the most different on shifting feel. Look down on this page for pics:
http://www.miata.net/garage/trans/everything.html
It’s pretty easy to do, shouldn’t take more than 15 minutes after the first time, and all you need is a syringe with a bit of tubing on the end to suck out the old fluid.
June 7th, 2009 at 08:41
Well I’ve already got that pump so might as well use it to pump out the old fluid…
Any recommendation on oil for the shifter turret? Should I use the same stuff (Motorcraft XT-M5-QS)?
June 7th, 2009 at 17:14
yup same stuff should work just fine
May 20th, 2010 at 19:59
Enjoyed every bit of your article post.Much thanks again. Much obliged.
June 3rd, 2010 at 11:56
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