Automatic transmission longevity: fluids & OCI

[DoubleWasp]

Originally Posted By: akela
The dramatic change is what poses a risk, I guess.

The transmission likes when the fluid properties are stable. And doesn't like when they suddenly change - the mechanism needs to re-adjust, at a cost.


Not true. I've done complete exchanges on transmissions that had never seen one in 100k miles, and none were the worse for wear. All of those transmissions received or had external filters, however.

 

[wgtoys]

Been changing the ATF every 30k miles on both our 2003 Accord and 2006 TSX since new. Now at 175k miles on the Accord and 145k miles on the TSX with no signs of transmission troubles yet. The both still shift like they did when new.

Originally I was a stickler about using Honda OEM fluid (the old Z1 formulation), but it was getting off-odor by the 30k miles mark. Then I switched to Castrol Import Multi-Vehicle or Valvoline Maxlife Multi-vehicle. Both have had no noticeable shifting quality difference from one to the other.

I'm going to try the improved Honda synthetic ATF on the next change out just for grins.

 

[nicholas]

The transmission likes when the fluid properties are stable. And doesn't like when they suddenly change-------

So much misinformation in this thread - - - - - honestly.

 

[nicholas]

Changing the fluid in ANY automotive system - will have a positive outcome. Changing the fluid will keep the properties and characteristics STABLE - leaving it in to degrade and fill with contaminants will not.

Many of the comments in this thread simply do not make sense---- just old grandpa adages handed down through generations.

 

[hattaresguy]

Transmissions fail due to usage and inherent mechanical flaws.

I have never seen a transmission fail due to the fluid not being changed or failing.

Unless it was in the context of, "yeah the oil cooked in the transmission towing a 30k equipment trailer up grade with the F350"... yeah well that's more of a usage problem than a fluid issue right their...

My vehicles happen to be lifetime fill but I no longer service automatic transmissions for normal use.

 

[Warstud]

Originally Posted By: hattaresguy
I have never seen a transmission fail due to the fluid not being changed or failing

That's the first time I ever heard anyone say that.

 

[turtlevette]

Originally Posted By: Warstud
Originally Posted By: hattaresguy
I have never seen a transmission fail due to the fluid not being changed or failing

That's the first time I ever heard anyone say that.



The 700r4 in my vette started shuddering then after a few more days wouldn't go into gear anymore. The pump was whining. I changed the fluid and filter and put in Lucas trans fix to clean things up and it went back to completely functioning properly. I'm a believer in regular partial fluid exchanges now.

 

[Rolla07]

Ive drained and filled 3-4 times since i bought it with 50k miles. Im going to continue doing a drain and fill every 60k miles going forth. I drive the car pretty hard at times, no issues yet..knocking on wood...

 

[DoubleWasp]

Originally Posted By: hattaresguy
Transmissions fail due to usage and inherent mechanical flaws.

I have never seen a transmission fail due to the fluid not being changed or failing.

Unless it was in the context of, "yeah the oil cooked in the transmission towing a 30k equipment trailer up grade with the F350"... yeah well that's more of a usage problem than a fluid issue right their...

My vehicles happen to be lifetime fill but I no longer service automatic transmissions for normal use.


And you say this despite the fact that many of the "lifetime fill" transmission manufacturers have now backed off of that claim after dealing with plenty of warranty issues due to fluid being run too long.....

 

[Leo99]

Originally Posted By: DoubleWasp
Originally Posted By: hattaresguy
Transmissions fail due to usage and inherent mechanical flaws.

I have never seen a transmission fail due to the fluid not being changed or failing.

Unless it was in the context of, "yeah the oil cooked in the transmission towing a 30k equipment trailer up grade with the F350"... yeah well that's more of a usage problem than a fluid issue right their...

My vehicles happen to be lifetime fill but I no longer service automatic transmissions for normal use.


And you say this despite the fact that many of the "lifetime fill" transmission manufacturers have now backed off of that claim after dealing with plenty of warranty issues due to fluid being run too long.....


Has Toyota backed off those claims?

I'm still trying to gather data comparing untouched lifetime ATF to maintained ATF and I'm unable to find any data that shows changing the data will extend the life of the tranny.

I read a post on here a week ago that said the ATF failed but the tranny was fine. Have no idea what was meant by the fluid failed.

 

[nicholas]

I have never seen a transmission fail due to the fluid not being changed or failing.

Any reputable transmission shop will disagree with this statement -

I personally know of many, friends/acquaintances, whom lost their transmissions with dirty contaminated OEM fluid. Solenoid and clutch pack issues.

I honestly will never understand the idea of not changing the fluid in a system that has a very poor filtration design. Especially given the ease and simplicity to change the fluid in most ATF systems.

Also - when you change the fluid you can inspect the magnet and fluid for abnormal debris - - possibly saving components before catastrophic failure.

It is a win/win for me.
I routinely change ALL the fluids in my vehicles - not just the engine oil.

 

[meborder]

Originally Posted By: Leo99
I read a post on here a week ago that said the ATF failed but the tranny was fine. Have no idea what was meant by the fluid failed.


I'll give an quick example.

The factory fill of mercon in my 95 third had failed when I purchased it at about 90k miles. The torque converter shuttered badly upon lockup.

A fluid exchange with synthetic fixed the problem 100%.

Fluid failed, transmission is fine.

 

[Leo99]

Originally Posted By: meborder
Originally Posted By: Leo99
I read a post on here a week ago that said the ATF failed but the tranny was fine. Have no idea what was meant by the fluid failed.


I'll give an quick example.

The factory fill of mercon in my 95 third had failed when I purchased it at about 90k miles. The torque converter shuttered badly upon lockup.

A fluid exchange with synthetic fixed the problem 100%.

Fluid failed, transmission is fine.


Ok, it wasn't clear to me in the original post that there were any observable symptoms.

All to often I read posts on here where people seem to be more worried about the fluids than the mechanical parts themselves.

 

[turtlevette]

I wonder how many people have paid for full rebuilds when a fluid change might have cleared things up.

 

[meborder]

A full rebuild was recommended to me when I asked a transmission shop about it.

Went for the fluid exchange instead.

In full disclosure, I'm not sure what original post you were referring to, but rather adding my own personal story/experience.

 

[DoubleWasp]

Originally Posted By: Leo99

Has Toyota backed off those claims?

I'm still trying to gather data comparing untouched lifetime ATF to maintained ATF and I'm unable to find any data that shows changing the data will extend the life of the tranny.

I read a post on here a week ago that said the ATF failed but the tranny was fine. Have no idea what was meant by the fluid failed.


I'll add another example.

Friend of mine had a Ford Taurus that she owned since new. At about 87k miles, she reported transmission problems. The transmission would shift erratically, slam-shift at any time, and also go into lockup whenever it felt like it, even at 5 mph, or at a dead stop. Sitting at the traffic light, it felt like an elephant was ramming the car from the back as the transmission was trying to lock up and force the car forward. Releasing the brakes resulted in a nasty chirp of the tires, and gear hunting like Elmer Fudd after a wabbit.

Doing a cooler line exchange of all fluid turned it back into a very well behaved transmission that lasted another 78k miles until she sold the car.

Other known issues?

Clogged passages due to solid contaminant
Stuck check valves/solenoids due to solid contaminant
Torque converter clutch shudder (which will result in transmission destruction) due to worn fluid
Slamming/excess wear of clutch packs due to worn fluid which usually leads to mechanical destruction of other components and then failure

 

[Olas]

"lifetime fluid" = preplanned obsolescence.

 

[demarpaint]

Originally Posted By: Olas
"lifetime fluid" = preplanned obsolescence.


For sure!

 

[Smokescreen]

I do a pan drain yearly on each vehicle. The ATF always looks new going in and coming out. I have never had a transmission issue or even a hiccup with this regime in any of my vehicles that I have ever owned. I just figure you keep the fluid in good shape and the trans will perform as it should.

 

[philipp10]

Originally Posted By: nicholas
Changing the fluid in ANY automotive system - will have a positive outcome. Changing the fluid will keep the properties and characteristics STABLE - leaving it in to degrade and fill with contaminants will not.

Many of the comments in this thread simply do not make sense---- just old grandpa adages handed down through generations.


well this whole thread is [censored]. There are far too many variables to learn ANYTHING from these posts. The real data we need is hidden away in the engineering labs of GM, Ford, Honda etc. For all you know, maybe the fluid in a Toyota (lifetime claim) really does not degrade. But you'll never convinced the old timers here even though they have no proof it does.