How Often to Drain and Refill AT's?

[raytseng]

It depends on how expensive this is to you in time and money.
If its just toyota type t IV and takes you just 5extra minutes while you do your own oil change then every 2nd or 3rd oci can make sense.

So even though 30k should be more than fine, doing it every 15k or more often makes sense if fluid change history is unknown, and because it is so cheap. Just like getting new valve stems and valve cores with new tires even if the old ones could be reused. Or changing the oil filter even though it could go longer because you already are under the far and its all jacked up

But id you have to go out of your way and pay 60 and 2hrs then definitely not worth it to do it under 30k miles. Spend that time and money doing something else or on other maintenance you csn obsess over

 

[raytseng]

Originally Posted By: Donald
Add a Magnefine inline filter.

What your really doing is just refreshing the ATF.

From a cost and transmission perspective you would be better off doing a cooling line exchange every 50K and getting 95% of the old ATF and its contaminants out.

Your removing a small portion of the contaminants, diluting what is left, and then adding more as the vehicle is run.

You should find the spreadsheet calculator that has been floating around this forum and run through it to see how your doing. Many transmissions are 12 QTs, so your taking out at the most 25% each time.

The more expensive the ATF the less sense it makes to do what you are doing.

Amsoil is excellent ATF, its in my Jeep and pickup, but I mainly do cooling line exchanges.


i don't agree with this perception, esp. the spreadsheet theory and doing multiple d/f all at once. Although I completely understand some people feel they should do it this way, just as they feel they should dump the factory fill after 500miles.

The folks that go with the change it all like to feel warm and fuzzy that they've gotten in almost all fresh fluid, and they envision the "old" fluid is somehow some completely contaminated mess. But if you follow that vision, that means the miles prior to the change you were driving on that same contaminated bad fluid.
So assuming if you try to follow that train of thought, over the lifespan of your miles you fluid isn't necessarily better.

I subscribe to the gradual refresh theory. Yes the fluid will never be 100% new, but it won't be degrading as much either.

Say your fluid quality is 90% after a d/f change, it goes down to 80% your partial refresh brings it back to 90%, and so you're always operating at 80-90% quality fluid.

With the try to change it all strategy, you are envisioning that the fluid quality going down to say for example 50% and all of it getting dumped and getting back to 99%. That's why it doesn't make sense to me, because that means you got way more miles on worse quality fluid then the refresh strategy.

To me, to stretch this analogy like saying you should completely use up all the gasoline in your tank because it's going bad and will mix with the new gas.

So up to you what's better, but remember the miles just before the change, and not just the initial miles after the change.

 

[Donald]

Originally Posted By: raytseng
Originally Posted By: Donald
Add a Magnefine inline filter.

What your really doing is just refreshing the ATF.

From a cost and transmission perspective you would be better off doing a cooling line exchange every 50K and getting 95% of the old ATF and its contaminants out.

Your removing a small portion of the contaminants, diluting what is left, and then adding more as the vehicle is run.

You should find the spreadsheet calculator that has been floating around this forum and run through it to see how your doing. Many transmissions are 12 QTs, so your taking out at the most 25% each time.

The more expensive the ATF the less sense it makes to do what you are doing.

Amsoil is excellent ATF, its in my Jeep and pickup, but I mainly do cooling line exchanges.


i don't agree with this perception, esp. the spreadsheet theory and doing multiple d/f all at once. Although I completely understand some people feel they should do it this way, just as they feel they should dump the factory fill after 500miles.

The folks that go with the change it all like to feel warm and fuzzy that they've gotten in almost all fresh fluid, and they envision the "old" fluid is somehow some completely contaminated mess. But if you follow that vision, that means the miles prior to the change you were driving on that same contaminated bad fluid.
So assuming if you try to follow that train of thought, over the lifespan of your miles you fluid isn't necessarily better.

I subscribe to the gradual refresh theory. Yes the fluid will never be 100% new, but it won't be degrading as much either.

Say your fluid quality is 90% after a d/f change, it goes down to 80% your partial refresh brings it back to 90%, and so you're always operating at 80-90% quality fluid.

With the try to change it all strategy, you are envisioning that the fluid quality going down to say for example 50% and all of it getting dumped and getting back to 99%. That's why it doesn't make sense to me, because that means you got way more miles on worse quality fluid then the refresh strategy.

To me, to stretch this analogy like saying you should completely use up all the gasoline in your tank because it's going bad and will mix with the new gas.

So up to you what's better, but remember the miles just before the change, and not just the initial miles after the change.


I was not suggesting multiple d/f's at once rather do it via a cooler line exchange.

But your method always leave a significant amount of contaminants in the ATF. If you have 12 ppm of aluminum, drain and refill 25% you now have 9 ppm after you add the new ATF back in. Now you run the vehicle and you are building up the ppm's starting at 9 ppm.

If you do a cooler line exchange you probably get the PPMs down to less than 1, as its difficult to do a 100% fluid exchange in a vehicle, so it will never be zero. So running the vehicle now you are building up theppm's starting at less than 1.

 

[raytseng]

well, if that's the scenario, my point is then I'd prefer to do a d/f before you got to 12ppm. so it would always stay at 5ppm and get d/fed to 4ppm four times over the 60k interval; rather than letting it go 1-> 12 in the first place over 60k...

so 60k miles at 5ppm, versus (15k at 1ppm, 15k at 4ppm, 15k at 8ppm, 15k at 12ppm)

If the complaint is that the 5ppm is somehow undesirable, then what about the 8ppm or 12ppm in the suggested alternative?

If you say the intervals or example ppms are off, make the same alternations to the example with the d/fs.

Especially if a d/F is just 5min extra during an oil change, versus a more complex procedure.

 

[slacktide_bitog]

Every 30k or so.

On cars like new-ish Hondas where they have a MM, I change it according to the minder.

 

[ARB1977]

30K on the honda. 30-60K on the toyota.

 

[itguy08]

30k on our Fords and it seems to be working great.
Got 155k on the CD4E in the wife's Escape - was shifting fine when we traded it
97k on the 6F55 in the SHO and it shifts perfect
67k on the 6R80 in the F150 and shifts fine, even with 9k LBS in tow.

Cost about $120 at the dealer. Cheap insurance, IMHO.

 

[turtlevette]

Originally Posted By: itguy08
about $120 at the dealer. Cheap insurance, IMHO.


$2 valvoline synthetic from az clearance, much cheaper insurance.

 

[GaleHawkins]

New ATF where 2-3 quarts at a change or a total flush change by the bucket flush I think is helpful to the life of most transmissions.

We just did a Seafoam Trans Tune bucket flush on our new to us 2006 Ford Five Hundred with the six speed Aisin Warner AWF21`transmission that requiress the Mobil 3309 ATF that is repackaged for different car makers.

At 110K miles is still looked dark reddish and smelt OK. We used a 12 quart case and it took 3.5 quarts to top off after the last pump down cycle.

For the heck of it I added 16 oz of Lubegard Platinum. It should be good for the next 110K miles I expect but at the cost of $75 for a total fluid change out if we plan to keep the car we may do it again in 60K to play it safe.

Dumping in a quart of Lubegard Red over time when topping off may be all that is needed but I am new to Lubegard. Keeping all of the internal parts clean I think is key to long transmission life. If Lubegard actually drops ATF by 20 degrees that could double the life of the ATF itself per some charts but I do not know if that is science or marketing hype.

 

[MolaKule]

Another discussion on almost the same topic:

http://www.bobistheoilguy.com/forums/ubbthreads.php/topics/3928313/1/Automatic_transmission_longevi

 

[EA82]

On my van I've been doing drain and fills every 25k, I'd like to do the same on our camry but they make it difficult to do it, it's starting to shift funny with only 40k on the clock.

 

[dblshock]

I extract then replace 3qts. from the dipstick tube every season..do the power steering reservoir right away too.

 

[MaximaGuy]

30K seems like a reasonable period that has worked fine for me for ages on my vehicles until I decided to get a fancy Lexus.

What is annoying me is my stupid Lexus (w/ 46K on the odometer) has a freaking complicated tango to get the freaking level right.

 

[supton]

Wouldn't driving schedule come into play?

I drive >25k/year, mostly highway. Not towing, 14qt capacity. I'd think 50k would be just fine, easily, for my trans, at least after an early exchange.

 

[bdcardinal]

My mom's 2014 Fusion got a free fluid change at around 7K because the pan gasket (RTV) was leaking. She is just past 15K so I need to get her oil change done. I might do a drain and fill when I have it in the air. The 3-4 quarts of LV are a lot cheaper than a 6F35.

 

[sw99]

I do the drain and fills yearly. Fluid is cheap.

 

[Bgallagher]

If it is a drain and fill and your everyday car I would do it once a year or 10k if you are using a conventional, 20-30k if a part or full synthetic. The way I figure is the fluid is cheaper than a new transmission. Do it more often.

 

[Oro_O]

Originally Posted By: MaximaGuy


What is annoying me is my stupid Lexus (w/ 46K on the odometer) has a freaking complicated tango to get the freaking level right.



If you are talking about the silly electrical read-out nonsense Toyota started spec'ing after about 2004/5-ish, do what most mechanics and dealers do - ignore it.

It is a lot of nonsense to just get you to the same point as before, checking the fluid while warm and then fill until it levels at the fill port. Dealer mechanics report they don't do it either, just idle the car 15 minutes and then check the fill/top it off.

 

[MaximaGuy]

Honestly, it isn't that straightforward. The pan has a drain bolt that drains the excess ATF, the level check is a small plastic thingy threaded above the drain bolt. Unnecessary hi-tech gizmo when a dip stick would have done the job.

 

[wander2039]

The Escape and Focus both get 50k intervals with Mercon V and Lubeguard Red.

The RV is gets 10k (every other oil change) with Maxlife and Lubeguard Red. 13-15k lbs and might start towing the Focus. Plus it's a Chevy.. needs all the help it can get.