Most practical Type M5 ATF?

This is drain and fill for a post 2012 Mazda5 - they use Type M5 ATF - there are a lot of options - what would be most practical ones:

  1. Synthetic - Redline D4 Automatic Transmission Fluid (ATF) $48

  2. OE Equivalent are BECK/ARNLEY and Aisin -($28 for a gallon),2013,5,2.5l+l4,1506101,transmission-automatic,transmission+fluid,11387

  3. Synthetic - Pentosin - $70

  4. Synthetic - Motul (Article number 103221) - about $46

  5. Synthetic - Valvoline MaxLife Multi-Vehicle - $18

  6. Castrol 03521 Transmax Import Multi-Vehicle $24/gal

OEM Mazda fluid is about $15 a quart. Why not just use the OEM fluid and sleep better at night? The fluid change interval can’t be frequent enough to be sweating about the slightly higher cost. Are you looking to save $10 to $50 over 60,000 miles? It hardly seems worth it.


OEM pointers:

  • not Synthetic
  • Mazda enthusiasts seems to dislike OEM but use Castrol, Redline, Motul. They are majority of them - they tried many of these ATFs on the same car.

No direct experience with M5, but I use Valvoline Type F in my Ford truck and never had a problem.

IMHO the best bet with coolant and especially tranny fluid is to use only OEM fluids.
Try other fluids and you risk coming back here asking how much it costs to replace a transmission.

The most knowledgeable people for your car’s needs are the engineers that designed and tested it. And the design team are the ones that created the spec sheet from with the tech writers that wrote your owner’s manual got their information. Nobody on any internet site knows better than they what’s best.

That’s my story and I’m stickin’ to it. :stuck_out_tongue_winking_eye:


Isn’t that like saying, “I use bear grease on my stagecoach axles and never had a problem”?



So Synthetic alternative for ATF is also not good!

BTW, Dealer told me that my Mazda5 (2013) uses ATF for the power steering as well! I may have to double check.

The computer that controls a modern automatic transmission or transaxle has its algorithms based on fluid with very specific characteristics. Stray from those characteristics and the result could be anything from rough shifting to the very early demise of the clutches.

Always go with OEM-spec fluid.

Thanks all.

A totally unexpected perspective. Thanks.

Honda Trannys have been weak - so I have been using Honda ATF every 2yrs on my Hondas - because Mazda said type M5, I was thinking another M5 might be better. It looks like I will be continuing with the OEM fluid then.

Having moved to Synthetic for engine oil (including on my 80s honda), I somehow had a mindset to use another fluid - especially one is better (synthetic), costlier, what enthusiasts are using etc.

I wouldn’t necessarily call them weak because the manual tells you to change the fluid in them 2yr/30k miles. They certainly are more picky in regards to the type of trany fluid, that is true.