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Automotive Help - Can anyone identify these transmission parts?

  1. Nov 19, 2016 #1

    jim hardy

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    My transmission experience is with old Borg Warner overdrives in Fords of 1950's.
    I've never had apart a modern automatic transmission.

    We changed the oil in son's automatic transmission today, a 2001 Ford Explorer (4.0l v6 4wd) .
    Oil was dirty , but no bronze or metal shavings in filter just the fine powder-sludge you expect to find on the magnet.

    But we found five of these little discs in the bottom of the pan. They're non magnetic.
    It shifts way more smoothly after the oil change, emits no strange sounds.

    Does anyone recognize the little discs? If so, are they harbingers of doom?
    four shown, one is in the grass. you know how that goes....


    old jim himself
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  3. Nov 19, 2016 #2


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  4. Nov 20, 2016 #3


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  5. Nov 20, 2016 #4

    jim hardy

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    Thanks guys

    OCR nailed it it's the spacers for the pan gasket as explained on those Ford forums..


    which suggests to us that transmission still had original filter and oil after 178,000 miles . Must be a pretty good one.
    We opened a line at oil cooler and flushed the transmission with about eleven quarts of new fluid to get it coming out clean.
    Shifts like silk now.. Keeping fingers crossed.... if it works as well as it seems so far it was a hundred dollars well spent .

    thanks again guys , i would have obsessed over those little disks. New gasket either doesn't have them or they are covered and don't show .

    old jim and Tom hardy
  6. Nov 20, 2016 #5


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    :ok: ...
  7. Nov 20, 2016 #6
    "original filter and oil after 178,000 miles"

    just a note re this and flushing.

    Factory flushing can be too good/forceful for a transmission that has not been regularly flushed because it is possible to dislodge caked in deposits that have later been known to cause catastrophic failure.

    A softer flush where the total fluid content is gradually replaced by repeatedly diluting the total volume to about 3 % of the original dirty fluid is much gentler. ie change the fluid, run for say 100 k's. change again and repeat about 5 times.

    With the last change, replace filter, clean magnets and replace gasket
  8. Nov 22, 2016 #7

    jim hardy

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    That's something i've wondered about.

    When i've taken one to the shop they drop the pan, replace the filter, replace pan and refill. That only gets rid of the couple quarts in pan and whatever drains from gearbox yet book says capacity of this transmission is 10.5 quarts.
    It was so black and smelly we decided to do a complete change if we could. Couldn't find a drain on the torque converter so we figured a flush was best we could do without dropping the transmission.
    With engine idling and cooler hose disconnected we let it pump out all the fluid it would , which empties the pan to below the pump suction on bottom of filter housing
    Then we repeatedly added two quarts , let it pump that out into an empty five gallon oil jug from a restaurant we were using for a catch vessel. The eighth quart was noticeably clearer, by eleven it looked clean.
    So i doubt we achieved 3% but perhaps 10%.
    Took four more quarts to fill it back up to the dipstick's 'full' mark. I guess that's the capacity of the oil pan.

    Now the last ATF fluid i bought was $2 a quart now it's six. But there's no inflation, right ? That's why this ran up to a hundred+ dollar job instead of thirty..
    Oh well it still beats a $1500 rebuild.

    I'm a believer in changing ATF every 50K miles. It keeps the elsatomers in good condition.

    There's nothing like projecting with your kids. I raised them all to be DoItYourself-ers. My eldest daughter is fearless, she tore into electric windows on their fancy truck to astonishment of the guys at at Ford parts desk.

    old jim

    ps apologies for the non-scientific bent of this thread.
    The point about dilution is significant though ,
    maybe that's why transmission shops recommend change every 35Kmiles - that'd be a ~40% change on this vehicle which might work well if done often enough..
    old jim
  9. Nov 22, 2016 #8
    We could make it a bit more scientific by introducing the concept of Serial Dilution : http://biology.kenyon.edu/courses/biol09/tetrahymena/serialdilution3.htm

    I made a worksheet that allowed the insertion of total transmission volume and usual change volume and produced a graph whereby I could see by which iteration of dilution an acceptable (to me) dilution had been achieved. Unfortunately that's a couple of OS installations ago and no backup, however not difficult maths.

    When I said 100k's I meant 100km's.

    I agree re DIY. Big savings. (eg. to change a timing belt on my Magna (Diamante in the US) I'd have to pay over a 1000 to a mechanic to do it. The part only costs about 100. With a bit of preparation I do it myself in a day. A lot of perfectly good vehicles end up at the tip or wreckers because people decide by that time to put that 1000 into a 'new' car (with new problems))
  10. Nov 23, 2016 #9
    another note: I found the black colour very persistent. The best I could get colour wise was a dark red. However re the serial dilution maths I knew it was good enough after 5 iterations on my transmission. I kept a sample of each change with intention of doing various tests like specific gravity, viscosity, light transmission etc to work out a way of determining quality of fluid from dip stick. Never got around to it but I still have the samples. I think smell burnt or rancid compared to new, even a kind of rank fear smell indicates it's perhaps no good. The feel of it between fingers. It can be hard to determine colour from such a small sample. I found I can jiggle a thin plastic tube down the filler tube and draw a small amount up to inspect.
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