Flush vs drain/fill when going to synth

[jonnybearback]

Mazda5, recommended by dealer to flush. Which is fair based on the Mazda m-v fluid getting burned easily and their assessment of fluid is same as mine.. burned brown

But, reading around these transmissions, it appears that moving away from Mazda m-v is a good idea. M1 synthetic and Amsoil atf seem to tick the box as approved, but, when switching to synthetic, does it need a complete purge and refil (flush swap)?

Or, castrol import multi is a good price point alternative approved for use in that box.
So, better to drain and fill with this rather than flush through for a synthetic atf?

I've one experience of a flush.. cost me a new transmission inside 800kms so I'm a little hesitant to flush.

(2010 mazda5 57,000kms, original atf, 72mo 120k warranty)

tia for help with miscibility of syn/non syn fluids

 

[V8man]

How many quarts of fluid does your transmission hold?

How much fluid can you get out on a pan drop?

 

[Rhymingmechanic]

Does it have a drain plug? If I were doing the work myself, I would drain and fill three times and then drain and fill at regular intervals. If it has a serviceable filter, you could drop the pan and change the filter on the last change.

The drain plug method won't replace 100%, but is a lot easier. With no plug, the flush is the best way to change the most fluid.

I don't know about these transmissions and whether they're prone to failure. If that's the case, consider your warranty when you pick a fluid. (Make sure it is "approved" for your application, not just "recommended.") Also document your work/save receipts. Since the dealer has already recommended a flush, they might give you a hard time if the trans begins acting up.

 

[jonnybearback]

Pan has a drain plug and holds about 3 qts
Fluid capacity of teh transmission is 8.6qts

Quote:
Since the dealer has already recommended a flush, they might give you a hard time if the trans begins acting up

Yep, thats my biggest challenge.. at least if they flush and it goes belly up, I'm covered I guess.
After that, I'm at least starting on a clean atf slate if I do swap to synthetic or non mazda oem atf.

Still concerns me after prior flush experience though.

 

[quint]

Do we really know if this fluid is 'burned' or if it merely turns back to its true original color because the dye has simply faded? I hear a lot on car forums that Mazda MV (and its Ford equivalent FNR5)'burns' easily, but I have yet to see a used oil analysis to show that the fluid really is burnt.

And are you sure Mobil 1 is still recommended for Mazda MV (not to be confused with Mercon V)? I know a lot of people use it and report no problems after extended use, but I have only seen one bottle that specified it, and it was an obviously old bottle, waaaay in the back, covered in dust. The newer bottles didnt contain the Mazda spec in the list.

And to echo what was already mentioned about the warranty....I have read (but not experienced first hand) that Mazda can be stinkers about analyzing fluids used, if an engine or transmission fails under warranty. Beware, just in case this is true ( I have no idea if it is or not). We have the 100k warranty on ours, my drains and fills until the warranty is up will be dealer-purchased fluid, just to eliminate any shenanigans if there is a failure. Its not cheap by any stretch, but even figuring the $4 per bottle premium over Mobil 1, I dont think I'll use enough between now and the end of the warranty to justify the paranoia I will have if something fails with a non-spec fluid.

 

[jonnybearback]

So, in all reality, to avoid being sent through the wringer by Mazda IF there is a failure.. flush at the dealer with dealer service receipt and moving forwards, DIY drain and fills with Mazda m-v to keep it 'red' until warranty expires is my best approach for a worry free life.

Makes sense

 

[quint]

Thats my personal course of action. Its certainly not the cheapest one, but its certainly the safest, as far as keeping the warranty intact. And the paranoia I'd be under using a non-spec fluid while under warranty (no matter how much I see on various forums that they perform fine in this application) would make me bonkers. And I'm a little bonkers to begin with....

 

[Jim Allen]

Total fluid exchange with a pan filter (if so equipped). No half measures IMO. In that many miles, there is a lot of contamination buildup and that is more than 50% of the reason to change the oil.

"Flush" is a bad word. It can mean one of those silly and destructive backflush things or just a generic term for a fluid exchange. Verify it's the latter and do it.

 

[jonnybearback]

According to teh service tech.. they have a machine hooked up to the cooler lines and it replaces all the fluid with new. they only put mazda M-V atf fluid through the transmission.. no additives or 'snake oils' fluid travels in teh direction of normal operation..

$149.00.. booked in
... doesn't include a pan drop and its a strainer not a filter. but that'd be another $100 parts plus however much labour so I'll see how the fuid exchange goes first.

Thanks muchly!

 

[GC4lunch]

Originally Posted By: jonnybearback
Mazda5, recommended by dealer to flush.

M1 synthetic and Amsoil atf seem to tick the box as approved, but, when switching to synthetic, does it need a complete purge and refil (flush swap)?

Or, castrol import multi is a good price point alternative ...

I've one experience of a flush.. cost me a new transmission inside 800kms so I'm a little hesitant to flush.


I'm with you on hesitancy to do a complete exchange. A few months back, we performed a 3X drain and fill on our 2004 Mazda6 (with a couple of hundred miles driving between the first and second stage and also between the second and third stage), and that technique seems to have worked perfectly (and required less new ATF than the complete exchange of fluid performed on the same vehicle five years earlier, though it was still a bit more new fluid than the total capacity of the transmission + torque converter: the "flush until it runs clear" requirement in a full fluid exchange sends a lot of virgin ATF straight to the recycling contractor).

If you lived in Japan, your Mazda dealer would recommend (more likely, not ask you, but simply install) Idemitsu Type M full synthetic ATF, than which there is no better fluid for this specific application. Fortunately, here in North America, that recommendation is not only just as good, but it is an economical best buy: High quality Idemitsu ATF synthetic Type M for $7.01/quart

 

[SteveSRT8]

Originally Posted By: jonnybearback
According to teh service tech.. they have a machine hooked up to the cooler lines and it replaces all the fluid with new. they only put mazda M-V atf fluid through the transmission.. no additives or 'snake oils' fluid travels in teh direction of normal operation..

$149.00.. booked in
... doesn't include a pan drop and its a strainer not a filter. but that'd be another $100 parts plus however much labour so I'll see how the fuid exchange goes first.

Thanks muchly!


This is the correct way. I always recommend a pan drop at the first service after JA posted the info on wear particle generation all happening in the first miles and declining thereafter.

Your own trans pump does the work, and done properly this will never harm a healthy trans, only help it last...