Originally Posted By: quint
Reading this thread with great interest as I have two Mazda's that require M-V/FNR5 fluids.
I dont trust the Maxlife recommendations for the only reason that so many confuse the Mercon V spec with the Mazda M-V spec. I have been on enough Mazda forums to see people using Maxlife or even Mercon V without problems, as in "I use it and it works fine", however "its working fine" and "its causing problems that simply havent gotten bad enough yet to notice" are eerily similar in real life and I dont know if I want to risk a $2000 transmission to save $5-$6 a quart in fluids.
I have yet to see Castrol, Valvoline, Mobil, or any other big name fluid carry the Mazda/Ford spec recently, at least not printed on the bottles. I considered using Mobil 1 ATF as it used to carry the FNR5/M-V spec (although it does not anymore as Tig mentioned) but when you compare the cost of Mobil 1 ATF versus simply buying the factory fluids from the local dealer, the cost is almost a total wash, its basically the same, at least at the dealers around me. My local Ford dealer has FNR5 for $9.50/quart and Mazda wants $11.50 for M-V.
I'll wait for a few more years of anecdotal forum postings about people using this or that ATF's before I bite the bullet and use anything other than FNR5/MV fluids from the local dealers.
What confounds me is that the trans in my Mazda2 is the same trans used in the Ford Fiesta, yet the Mazda requires Mazda M-V, while the Ford applications it specifies Mercon LV, which would lead one to believe that LV and M-V/FNR5 may have some interchangeability to it. But then why would Ford have two separate specs (FNR5 and Mercon LV) if they were interchangeable? While the specs themselves arent interchangeable, clearly in certain applications, there is overlap as far as what can be used in what. The only parts difference I have found between the two transmissions is the side cover plate and a pressed in bushing, the Mazda plate uses an aluminum bushing and the Ford uses a steel bushing. Is this enough to use two different fluid specs? Maybe it is, who knows.
This nonsense in the last 10-15 years with proprietary coolants and ATF's has gotten really annoying.
Thanks for the post. I'll just mention that Castrol does specify M-V in its PDS for Transmax Import fluid. Also, while comparable Valvoline ATF's PDS specifically says the list in the PDF file is not complete, some other documents from Valvoline do mention M-V. Now, how a multi-vehicle fluid can cover M-V, Mercon V, Dexron III, SP-III, etc all at once is still a mystery to me. It might be all very simple but I wonder if anyone knows of a document on that topic or a thread...