ATF Lacks Cleaning Detergents

[donjetman]

In case you don't know? atf has almost NO cleaning detergents. And why should it? There are no combustion gases and/or by products in a tranny. Engine oil has a lot of cleaning detergents in it.
ATF viscosity is thin, about like a 10-15 wt oil.

 

[intheburbs]

Yup.

This is "straight from the horse's mouth"....

ACDelco DEXRON-VI ATF is a high performance, synthetic blend formulation that meets or exceeds the
stringent requirements of GM's DEXRON-VI specification and provides warranty protection for current
GM vehicles. It also provides improved performance in older GM vehicles, wherever DEXRON is
specified.
ADVANTAGES:
Outstanding friction performance and stability
Enhanced frictional properties
Improved anti-wear protection which contributes to
Higher oxidation stability, thus higher ageing stability
“Fill-for-life" oil. e.g. developed for maximum drain intervals

Nothing about cleaning/detergents

 

[Dustin Jackson]

What are people doing with transmission fluid other than putting it in the transmission?

 

[B-train]

Interesting info. I've used it for years for many different things and it's always seemed to help improve fuel systems (early 90's cars fuel injectors that didn't like ethanol fuel, and for washing motors for sticky lifters, etc). I wonder if the older dextron fluids were a different makeup? Maybe the different blend of additives seems to be beneficial outside of a transmission?

 

[MWD_CTSV]

Dexron-VI is such a tough spec to meet, I think it can only be met with high grade PAO synthetic oil in high quantity. So that typically requires less additive to compensate for thermal decay and oxidation.

The additive package for ATF is quite a complex beast. The actual additives generally referred to as dispersants can have multiple properties such as friction control, antiwear, leakage control, aging control and cleanliness. Some additives can have positives in a small quantity, but negative in higher quantity, or interact with other additives in a negative or positive way.

Technically the dispersants have a detergent effect, and some refer to them as both, while the purists would say they are just dispersants. In some cases, the dispersants in ATF seem to be able to collect sludge and hold it in suspension at least visibly due to the color change in the fluid.

 

[MWD_CTSV]

Also I think some of the same dispersants for ATF are also used as 'detergents' for fuel additives.

Specific to percentages, the additive licensed for making Dexron-VI (Afton Hitec 3491LV) is recommend as a 10% blend, whereas their additive for Dexron-III is something more like 18%. That probably has a lot to do with compensating for the lower quality base oils in the older spec fluid, but it would certainly mean more dispersants. To a degree that should mean better cleaning I would guess.

FWIW, the SDS for Berryman oil flush says it includes 2-5% polybutenyl succinimide, which is the same ashless dispersant used in the best ATF additive packages.

 

[Marky Dissod]

What are people doing with transmission fluid, other than putting it in the transmission?

Don't some people put ATF in the engine crankcase to 'flush' it clean?
Never said that makes sense, just sayin' that I've heard that some people do it.

 

[intheburbs]

I'm not sure about the GMT900 body style, but I remember reading that the GMT800 3/4 ton body style Yukon XL's and the Suburbans had the Allison Transmission as an available option IF you got the 8.1 big block engine. It wasn't available with the 6.0 engine though.

Don't some people put ATF in the engine crankcase to 'flush' it clean?
Never said that makes sense, just sayin' that I've heard that some people do it.

Yeah, not sure if that's an internet myth, or there was actually something to it 20 or 30 years ago. I'd heard that too - just before an oil change, pour in a quart of ATF and drive a few dozen miles to "clean" the engine internals.

That said, I do usually run half a can of Seafoam in the crankcase for a few miles right before an oil change.

 

[B-train]

Yeah, not sure if that's an internet myth, or there was actually something to it 20 or 30 years ago. I'd heard that too - just before an oil change, pour in a quart of ATF and drive a few dozen miles to "clean" the engine internals.

That said, I do usually run half a can of Seafoam in the crankcase for a few miles right before an oil change.

As stated by @MWD_CTSV , I would say that older versions of the Dextron would have a better cleaning affect. I've used it with good results over the last 25 years for sticky fuel injectors, lifters that were noisy, etc. Interesting though, that the newer stuff has less of the dispersants (detergents) than the older versions. That may explain why it seemed more effective back in the day.

It does work, I still use some every few oil changes on both of my newer vehicles. You can physically see the oil color change in a short period as its cleaning out carbon/varnish from different areas or pieces of the engine internals. The oil always seems to stay cleaner longer after one of these changes.

Again, not a chemist, just someone who has seen the effects of using ATF in a different application over the years.

 

[swathdiver]

ACDelco DEXRON-VI ATF is a high performance, synthetic blend formulation...

The ACDelco Dexron VI that we use here is full synthetic.

 

[Charlie207]

Don't some people put ATF in the engine crankcase to 'flush' it clean?
Never said that makes sense, just sayin' that I've heard that some people do it.

I've seen it mentioned on this website a few times in the last year.

 

[j91z28d1]

I'm no chemist so I can't back this up with anything but a life time of working on cars.. atf will clean just about anything. I used to hate changing tranny filters on our fleet of c6 trannys because it's always a mess but when you're done and you wash the atf off, your hands are the cleanest they will be till the next time you do it lol.

I believe this is where the flushing comes from. if you've ever changed a tranny pan gasket and been covered with the stuff you'll see how it somehow breaks down years of oil build up from old school leaky engines.



I'm not going to argue about if it work or not, as said I've got nothing but my own experience and you will either believe it on not. but for anyone curious about it, this guy is good with these gm trucks and talks about how to do it correctly. it's not a toss a few qt in and go type of thing.

ATF For Engine Flush? Lets Talk About It Live

What are my thoughts on engine flushing? Can you use ATF to flush your engine? How do you do it?Click my coffee link and get yourself something to help suppo...

www.youtube.com

if your engine is decently clean, this isn't needed. this is for those crazy bad ones that probably should be rebuild. not a normal thing to do for sport like when people toss in a can of sea foam. both my ls engines have over 100k on them and are spotless inside and they have had nothing special done to them and no need for a atf flush. but if i picked up a used one full of gunk, I'd do it.

 

[Marky Dissod]

Not disputing anything, just starting to wonder if the above applies more to Dex3 instead of Dex6?
'cause GM changed the formulation, and all?

 

[Z15]

Dexron-VI is such a tough spec to meet, I think it can only be met with high grade PAO synthetic oil in high quantity.

Dexron VI IS NOT a pao synthetic. Its what is referred to as a Group III base stock, PAO is Group IV

Nothing GM branded is PAO.

The highest grade Dexron is Dexron HP in the 8-sp and Dexron ULV in the 10-sp

What are GTL Base oils?
They are synthetic paraffinic base oils obtained using Fischer-Tropsch Synthesis of natural gas.

GM Dexron HP

"The base stock of old fluid (19355656) has the ability to attract low levels of moisture, which can cause degradation of the coefficient of friction of the fluid. The new fluid (19417577) has a new GTL (Gas to Liquid) base stock that is able to tolerate more moisture. Shuddering transmissions and torque converters have been recovered with the new fluid. New transmission fluid tests have been developed due this issue to prevent it from occurring with new transmission fluids."

 

[Z15]

Don't some people put ATF in the engine crankcase to 'flush' it clean?
Never said that makes sense, just sayin' that I've heard that some people do it.

The concern of using an ATF in place of a flush is chemical incompatibility with engine seal material. ATF has been known to over swell engine seals and cause leaks and premature failure.

 

[tom3]

Used to use ATF in five speed manuals as listed in owners manuals. The Tremec TKO was originally spec'd to use ATF. I wonder if the new stuff would be better, or worse, in high pressure gear sliding contact and good syncro action?

 

[Z15]

Depends on what year and what ATF was called for.

Recommendation/Instructions:

Manual Transmission fluid part number 88861800 U.S. (88861801 Canada) is currently available through GMSPO. Current and past model vehicles listed above with either a manual transmission or transfer case that REQUIRE Dexron III should use the above listed manual transmission fluid. This fluid is a direct replacement for Dexron III in manual transmissions and transfer cases. DO NOT use Dexron VI in place of the manual transmission fluid in any manual transmissions or transfer cases as a failure may result.


"If fluid part number 88861800 U.S. (88861801 Canada) is unavailable when servicing a manual transmission or transfer case, Dexron III can be used in it's place. DO NOT use Dexron VI in place of the manual transmission fluid in any manual transmissions or transfer cases as a failure may result"

 

[Marky Dissod]

The highest grade Dexron is Dexron HP in the 8L90E

Is Dexron HP 'backwards' compatible with Dexron 6J?
By which I mean, is it okay to pour Dexron HP into my 4L60E - or would it be a mistake?

(PLEASE do not construe the above to mean that I WILL use Dexron HP in MY 4L60E!
Just wondering if this is a bad, so-so, meh, or good idea for anyone?)

 

[j91z28d1]

Used to use ATF in five speed manuals as listed in owners manuals. The Tremec TKO was originally spec'd to use ATF. I wonder if the new stuff would be better, or worse, in high pressure gear sliding contact and good syncro action?

it's my opinion that atf is a horrible manual tranny even when it's called for unless you're not going to drive it in any kind of way that is ******* synchro. it is to slippery and isn't thick enough to cushion between fast shifts.

you can't use old school gear lube because what's in it will eat up the glue on the friction material on the synchro. back in the days of the fox body mustang guys trying to push the limits of stock T5 trannys. which called for atf, they would put the old thick stp engine treatment stuff in them. it made shifting a bit harder but helped keep 3rd gear in them on the drag strip.


these days I run redline MTL in all my manual trannys that call for atf and they run cooler and shift better on track days. (not drag strip) but I've head good things about gm synchromesh fluid too.

 

[Just Fishing]

Interesting.
I attempted to use it to break up carbon a while back, it might have helped a little but not enough.

Then I get introduced to this Mopar+4 ATF, it has an almost gear oil stink to it.
I used that to break up carbon on the jeep engine rebuild.
I don't know if it helped, but I had a really easy time getting the carbon off of the pistons when using it.

It also did a great job removing light rust from Fastners.