2012 Mazda MX 5 Miata NC Manual Transmission Fluid Change

Changing the transmission fluid (oil) in a 2012 Mazda MX-5 Miata NC. This is a pretty straightforward procedure, but space can be a little limited in the transmission tunnel, so a short 24mm socket (I didn't have one handy) and fluid pump are very helpful. This is the second time I've changed the transmission fluid, the first time after about 30,000 miles, and the this time at just shy of 60,000. I don't race or track this car, so I could probably could have extended the change intervals out longer.
The Motocraft Full Synthetic Manual Transmission Fluid is highly recommended by many, but any quality GL-4 75W90 gear lube will work.
Thanks for watching!

[@quailstudios]

You helped me change my transmission and differential oil yesterday! One tip is to not take out the fill plug after making sure you can loosen it. Keep it finger tight when you open the drain plug and the oil will come out slowly and will fall straight down instead of missing the catching pan. Then, if you want, you can slowly loosen the fill plug if you want the oil to come out faster and be able to make sure it doesn't spill all over the place.

[@Zeck88522]

Torque Spec. (ft-lbs/N-m) Spark plugs 11-17 (132-204 in-lbs) Engine oil drain plug (19mm) 22-30 / 31-41 Gearbox drain plug (24mm) 29-43 / 39-59 Gearbox fill plug (square) 18-29 / 25-39 Differential drain plug (24mm) 29-40 / 39-54 Differential fill plug (23mm) 29-40 / 39-54

[@Zeck88522]

Differential drain plug (24mm) 29-40 ft lb

[@TheAfterWorkGarage]

Thank you for the info. That's extremely helpful!

[@kyrkbymannen]

Worth mentioning is also that this is a six speed transmission. My five speed looks pretty different underneath! :-)

[@TheAfterWorkGarage]

Excellent point. Thanks for pointing that out!

[@fatdoggolovespizza]

@@kyrkbymannen he did mention it lol

[@kyrkbymannen]

@@fatdoggolovespizza Perhaps i was half past sleep when he did? 😀

[@gupter99]

Great video thanks, this will be my next maintenance project for my NC.

[@TheAfterWorkGarage]

Thanks, hopefully you'll enjoy the results. Your NC certainly will enjoy the new oil!

[@FireManiac58]

This really is one of the best car tutorials I’ve watched, thank you heaps!

[@TheAfterWorkGarage]

Thanks! I appreciate it!

[@jameskelly956]

TYVM for your video! My shifting is starting to suck, so I'm going to Ford to pick up the stuff! Oh, and I'm glad to see where to put my oil catch pan! LOL

[@TheAfterWorkGarage]

Nice, I hope a fluid change does the trick for you!

[@jameskelly956]

@@TheAfterWorkGarage - The Ford MT Fluid is like a new car in a bottle! Wowza! And when I changed the 2012 transaxle fluid, day-am, did that stink like an overdue kitty litter box! LOL You should add to his video to NEVER take out the bolt on the passenger side of the MT.

[@TheAfterWorkGarage]

@@jameskelly956 Awesome, I'm glad it made that much of a difference. And thanks for the tip on the passenger side bolt.

[@bUtMyRiGhTs]

The Mazda L 2.0 engine is actually made by Mazda not Ford. The transmission was made by Ford. When Mazda and Ford split around 2012 Mazda redesigned the engine and called it skyactiv, yet Ford still utilizes the older technology of the Mazda L engine for their current EcoBoost products. Mazda actually still produces some Mazda L engines in Japan for use in Ford vehicles. Mazda no longer uses the L engine design in any of their vehicles.

[@TheAfterWorkGarage]

Thanks for the comment! I am not by any means an engine/manufacture expert, so thanks for setting the record straight.

[@kanatsizkanatli]

not quite right, it's supposedly a Mazda design but other companies may have been involved, ford definitely helped design it and they built it and developed it too.

[@foodparadise5792]

All the mazda skyactiv engines are not good actually. It's direct fuel injection which for sure to have carbon build up around the intake valves down the line.

[@kwl189]

@@foodparadise5792 how far down the line? I’ve driven direct fuel injection all my life and haven’t seen issues across the car’s lifetime?

[@kwl189]

Mazda SkyActive engines are superb from what I understand

[@mannysoto4824]

I changed my 2012 6 speed to the Motorcraft oil and it feels notchier than before. I'm going to wait for about $K miles to see if it gets any better.

[@TheAfterWorkGarage]

Hopefully it improves for you. Let us know if you find anything out.

[@guanqiaowang7586]

How is it now?

[@skypresident3550]

Excellent Video; however, I had trouble finding info on Automatic Transmission fluid changes. On the Manual Trans. there are Fill and Drain bolt (top-Bottom 23mm and 24mm) BUT on an Automatic Transmission there is a 24mm Top fill bolt (on the side) and a regular Transmission Pan drain plug "under" the transmission with a 9/16 bolt. Also the Side Top Fill bolt has a "rubber" washer gasket (NOT a crush washer) so just snug it to keep it drain coming out (wouldn't torque it hard). My 2007 Car Manual calls for JWS-3309 Trans fluid and I found three types on EBAY/Amazon...Mazda Fluid, Aisin ATF-OT4 and Idemitsu ATF Type M. Also the Automatic Transmission takes three and 1/2 quarts to fill. The rear Differential has two bolts 23mm fill and 24mm drain (both with crush washers and torqued to 25-33 ft lbs). I used Redline 75w90 gear oil..took less than 1 quart.

[@ericfleetwood6744]

I notice that you made certain that you could open the fill nut before you opened the drain nut. Always a good idea!

[@FireManiac58]

Thank you for reminding me :)

[@Evoluzione2]

If you're in the UK then DuratecNC do the best gearbox oil, it stops those difficult cold 1st to second shifts which is where the metal on the drainplug there ^ comes from.

[@peacems]

I wish this trans fluid was still $22/quart. It's doubled since I last did mine in 2016. Damn inflation!

[@fatdoggolovespizza]

Hi there thanks for the video. Where did you get that sweet little siphoning gadget you used to fill the oil? Thanks.

[@lukasrydelius6174]

2:10 A simple box end wrench should fit easy. They’re cheap too, and a better option than a pliers/channel locks

[@TheAfterWorkGarage]

Very true. Though sometimes when you're already under your car (and it's yours), you just work with what you've got.

[@XtruhSpecialK]

Is your Miata able to sit on four jack stands evenly? Trying to do this job but only seem to be able to get it to sit on 3 of the 4 stands (with a tiny gap in between the pinch weld and the 4th jack stand)

[@TheAfterWorkGarage]

Hi, as far as I remember, it did sit evenly. I usually jacked up on the bolts where the control arms attach, and place jack stands on the pinch welds along the side.

[@timjoo5690]

Did you end up using the leftover bottle, or is 2 full bottles plenty? I just got my first NC2 6MT and looking forward to doing this as my 5th and 6th seem a bit crunchy. Thank you!!

[@TheAfterWorkGarage]

Unfortunately to get the fluid to the proper level, you do need to buy 3 quarts. I had some left over from my last transmission change, so I got away with only buying 2 bottles this time. I'm not saying that you can't run with just 2 quarts, especially since you never totally drain out all of the old fluid, but for me I figure the extra $22 is worth not risking it. After all you don't change transmission fluid all that often.

[@mianjunabeats]

Great video! Just curious - do I need to worry about the torque numbers on either of these bolts when putting them back on?

[@TheAfterWorkGarage]

I'm sure there are torque values for these specific bolts, however I don't know them. I would say use a similar feel to the torque you would put on an oil drain bolt. You definitely don't want to strip out the side of your transmission, but you also don't want them to fall out.

[@azzcoopz3270]

I’m not sure exactly but they are usually about the same as a engine oil drain plug, about 25-30nm

[@foodparadise5792]

I would use a smooth jaw plier on the filler bolt next time. It's chewing it up.

[@TheAfterWorkGarage]

Good suggestion, yeah I suffer from use-what's-around-itis.

[@mje1625]

Thanks for the video! Quick question: Does the drain plug come from the factory with the magnetic end, or is it something that needs to be purchased aftermarket?

[@TheAfterWorkGarage]

Hi! The drain plug comes from the factory with a magnet. It's the only "filtration" the gear oil in a manual transmission gets.

[@rolandjimenez8529]

The BG Slick Shift synthetic gear oil is way better!

[@edwardbennet3902]

Wonder if anyone has looked into GM's " Synchro-mesh" fluid...?

[@TheAfterWorkGarage]

I have not heard of using that, but maybe someone has?

[@vasileiosloukidis209]

How much oil put ?

[@S30Uploads]

Can you help me find a crush washer

[@TheAfterWorkGarage]

Hi! I believe they are just a 14mm aluminum crush washer, so something like this: www.amazon.com/Aluminum-Washers-Gaskets-Replacement-9956-41-400/dp/B07GJN2GNZ/ref=asc_df_B07GJN2GNZ/?tag=hyprod-20&linkCode=df0&hvadid=463291187748&hvpos=&hvnetw=g&hvrand=18367713159784401069&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9026810&hvtargid=pla-1003892102154&psc=1 would probably work. If you have an auto parts store or dealership nearby, that would probably be your best bet.

[@mikemcguire513]

Is there a filter as well? Usually you should change the filter too

[@TheAfterWorkGarage]

With manual transmission there is usually not a filter. Automatic transmissions have filters because the fluid does double duty as a hydraulic fluid and has to be very clean for correct operation of valves/check balls/accumulators etc. In a manual transmission it's essentially just gear oil, so small amounts of contaminants aren't a problem.

[@thenameisjoker]

What color is your nc?

[@josedias2585]

My honda dirtbike takes 1 quart and a half of oil and that's 30$ motor oil haha 😅 not bad for something you do every 3 to 4 years I'd say

[@terenceacton5803]

Amature - water pump grips😱

[@sodapop9869]

I'm going to give this fluid upgrade a FAIL. Changed it out in my 2012 NC 6sp MT PRHT. No difference. Easy enough job but might be better off spending your time and money on something else.

[@charlesosbun3642]

A real mechanic wouldn’t use channel locks on a bolt head!🤢🤮💩

[@hokole565]

Disliked for women’s rights.

[@TheAfterWorkGarage]

Not totally sure what you mean here, but women can definitely change gear oil too!

[@kwl189]

Liked to cancel out your bullshit as feminist propaganda. Now take your suedo/neo feminism and piss off. The world is better off without your crap.

[@jagboy69]

@@kwl189 Epic reply. Maybe it's something in the water that turns them into man hating creatures.... Or she got majorly screwed over by some scumbag guy. Why she posted that nonsense on a gearbox oil video is beyond me.🙄

[@kwl189]

@@jagboy69 Quite possibly bro something in the water. Likely that she had negative experience with men at some point in her life. Absolute garbage posting that on a gearbox oil change video. Ironically I’ve had quite a lot of bad experiences with women in my life but it hasn’t affected me quite the same

[@jagboy69]

@@kwl189 PJW just did an excellent video on this issue. Perhaps she should watch this. kzbin.info/www/bejne/hoK6nZp8jsqLos0

[@particleinthewave8378]

How often do you change the trans fluid?