I'm looking to flush my transmission fluid in my 06 FEH with 61k miles. I've found a thread (https://www.greenhybrid.com/discuss/...01/index3.html) that outlines how to do the flush: drain plug, fill plug, and put the right amount of ATF in. Sounds pretty simple.

I'm not looking to engage in any spirited debates about CVT fluid change intervals or which ATF is best (within the spec recommended by Ford)...

I have a few additional questions:
- are there any filters in the transmission to change out, and is that something a non-professional mechanic can normally do?
- does a simple fluid flush as outlined above change ALL the fluid? (or does the torque converter retain some, as it would in a conventional transmission?)

Any thoughts or experiences would be appreciated.

 

You are aware that there are absolutely NO clutches in the e/CVT to provide ATF particulate contamination nor be a frictional heat source...??

No slippage, slipping, components whatsoever other than the "slip" in the electric motors between their rotors and stator.

 

Right on! No clutches and such in this unit. That's the beauty of it, the designers figured out how to use a planetary gear set to do the job and the computer adjusts the excitation, ICE power level, and frequency of the AC to the alternator & traction motor.

I couldn't determined if there is a filter in the transaxle so I believe there is not one. The wear inside that unit is minimal since it is all rotating stuff, but there will still be some small amount. My other concern is condensation inside it. I switched mine to Mobil One ATF early on (634 miles) and change it as prescribed.

As best I can see draining does drain all fluid. There are some good photos on the web with cutaway views and unless Ford designed in some retention catches for fluid all comes out.

I am considering a kidney loop filter setup. We'll see if I can make it work.

 

Are you sure the e/CVT runs in ATF and not just gear oil...??

ATF is basically hydraulic oil specially formulated to still provide a decent level of lubrication and to not hold debris, frictional clutch debris, in suspension.

With "just" gears it seems to me that lubrication would be the rule.

 

Look at the owners manual or shop manual for your FEH. Mine is a 2006 and calls for ATF.

So long as the design of the unit is for a certain viscosity oil it'll work. For example my 4WD Suburban transfer case calls for ATF while the front & rear axles both call for 75w-90 gear oil.

 

Cut away view of transaxle. Look at the front corner, I see no reason that all oil shouldn't drain so long as you have the front axle somewhat higher than the rear axle.

 

Here are the shop manual instructions for the 2006 FEH.

 

wwest:

Open up the shop manual pages attached in glennb's post: it calls for ATF for the transaxle unit.

Regarding "holding of debris" in suspension all lubricants (including ATF & hydraulic oil) are designed to retain "ash" (the term used by tribologists). The reason oil changes are called for is based on two things:

1 the depletion of additive package chemicals
2 the "filling up" of the capacity of the oil to retain ash.

If you install a very fine filter system you can extend oil life and if you sample the oil to monitor the additive package & chemistry you can extend life even more.

 

Before I change engine oil I always run the engine to get it up to operating temperature and have the oil, insofar as it helps, bring particulates into suspension.

In my lifetime I have had to drop very few oil sumps and even fewer ATF sumps, but my oil sumps have never had debris deposits on the bottom whereas EVERY ATF sump I have dropped has. The only debris, typically, in ATF would be from the frictional clutch material or metal particulate from gear tooth wear.

So engine lubricating oil is formulated, correctly so, to hold the byproducts, at least those that get through the filter, of combustion in suspension. To formulate ATF to do the same thing would be utterly stupid.

 

Once again you do not know what you're talking about.