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Transmission help!?!?

Druffner

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#1
Hello all, purchased a CPO 2020 Explorer ST last summer with 19k miles. No issues at all everything ran as it should, well I let Facebook pages and forums get the best of me talking about the trans being low from factory and blah blah so I had the fluid changed as a preventative measure and now ever since the fluid change the 3-4 shift is very hard depending on how hard you are on the throttle but it’s consistent, and there is the smell of trans fluid when sitting at idle after a drive and if the vents are on and you come to a stop the smell comes in the cabin.
So my question is, is it possible the trans was overfilled and that’s what’s led to these issues? Maybe the fluid is overfilled and getting on top of the planetary gears in the trans causing it to foam and vent out the top of the trans?
Next question for those who have messed with the trans fluid, how many quarts are needed to move the dipstick one number? I keep seeing ideal range at operating temp is 3-4.5 mine seems to be at 2.5 when warm. Any insight and feedback are much appreciated. Thanks.
 

Cruising68

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Level is important as is making sure the temp is at the proper temp. Many dealers won’t take the time to properly check. If it is significantly over or under filled bad things will generally happen. Before I did anything I would make sure the level is checked properly and adjust level. Don’t know the exact amounts but I’d say it was less than a quart for one number but nothing substitutes with the proper procedure to check, burnt hands and all


Sent from my iPhone using Tapatalk
 

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#3

UNBROKEN

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#4
Check the current fluid level following the proper procedure…let what you find out guide you from there.
 

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#5
So I have a question about this.
These instructions are quite precise, as they should be. And a wonderful resource.

Is the fluid level being checked with the engine running?
I know the old skool method was engine running, warm and in park. Just making sure.

Also, what diagnostic tool is being used to check trans temp? Will Forscan do it?

No, I didnt search, just responding as I was reading. :rolleyes:
 

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#6
So I have a question about this.
These instructions are quite precise, as they should be. And a wonderful resource.

Is the fluid level being checked with the engine running?
I know the old skool method was engine running, warm and in park. Just making sure.

Also, what diagnostic tool is being used to check trans temp? Will Forscan do it?

No, I didnt search, just responding as I was reading. :rolleyes:
Yes it should be running, Forscan should be able to do it.

See the first three steps of the level check procedure.
 

UNBROKEN

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There’s a PID for trans temp so you can also use any of the OBD scanner apps if you have one of those handy.
 

OP
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Druffner

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Thread Starter #8
Check the current fluid level following the proper procedure…let what you find out guide you from there.
Used an infrared thermometer and the bottom of trans pan was 210 after an hour drive home. Checked the fluid and it was between 2.5-3 car still has harsh 3-4 shift and I’ve confirmed that’s the gear that is troublesome by using manual mode and everytime I shift 3-4 it’s harsh. If full throttle from a stop when you get to the 3-4 shift it is a little delayed and the engine almost revs up a little more waiting on the gear to engage and then it slams in gear. All other gears shift smooth as can be. I took the car to my local dealer (who I normally don’t use, but this time it was more convenient) they stated there was nothing they could do because “no codes were thrown”. Is this the norm, or will I maybe have luck at a more reputable dealer close by? I understand that no codes may be present but clearly the shifting isn’t normal lol

how would you approach? Car has 28k on it, it’s a 2020 I have power train till 100k or 7 years from initial in service date as the vehicle is a CPO. I appreciate the help.
 

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#9
According to the Service manual you are on the low side of the correct fluid level, I would recheck it exactly following the service manual instructions using Forscan or similar scan tool to check the temperature, if still low then top it off following the service manual instructions, using the equipment specified by the service manual. If it's still hard shifting then I would suspect the fluid and proceeded to flush the transmission fluid using the fluid specified by the service manual, knowing that I may need to flush it a few times to flush all the old fluid out.

https://www.foexplorer.com/ford_explorer_general_procedures_transmission_fluid_level_check-779.html
https://www.foexplorer.com/ford_exp..._transmission_fluid_drain_and_refill-777.html
 

Cdubya

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So you bought it and it was shifting fine, then had the transmission oil changed and now it shifts poorly? Are you sure they used the right oil, Mercon ULV? Who did this service? Even dealers have been known to put the wrong fluid in but an Indy probably wouldnt even bother to source Motorcraft Mercon ULV and probably filled it with whatever they had on hand. Also, your dealer should check to see if you have the latest PCM firmware. The later PCM updates do shift better. Lastly, try resetting transmission adaptations. Some say this can be done by pulling the negative terminal of the battery for a few minutes. I do it with Forscan Lite.

Btw, a level of 2.5-3 using the proper procedures is slightly over but I'd be totally happy with that and wouldnt mess with the trans oil level.
 

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#11
According to the Service manual you are on the low side of the correct fluid level, I would recheck it exactly following the service manual instructions using Forscan or similar scan tool to check the temperature, if still low then top it off following the service manual instructions, using the equipment specified by the service manual. If it's still hard shifting then I would suspect the fluid and proceeded to flush the transmission fluid using the fluid specified by the service manual, knowing that I may need to flush it a few times to flush all the old fluid out.

https://www.foexplorer.com/ford_explorer_general_procedures_transmission_fluid_level_check-779.html
https://www.foexplorer.com/ford_exp..._transmission_fluid_drain_and_refill-777.html
Sorry I read the scale backwards, so I would have adjusted to a level that I was comfortable with, If it still hard shifted, I would have questioned the fluid.
 

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Druffner

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Thread Starter #12
Update to everyone, took it to the dealer and the tech checked the fluid level and it was good he then reset the adaptive learning for the trans and it instantly shifted better now here we are about 1,000 miles later and I can feel the 3-4 shift starting to get more rough with the more miles we put on it. I’m assuming something has to be wrong internally at this point?
 

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#13
Update to everyone, took it to the dealer and the tech checked the fluid level and it was good he then reset the adaptive learning for the trans and it instantly shifted better now here we are about 1,000 miles later and I can feel the 3-4 shift starting to get more rough with the more miles we put on it. I’m assuming something has to be wrong internally at this point?
IMO and from my own experiences, any calibration, or other software updates to a trans. that is experiencing issues has always been a temporary Band-aid. Not 1 time has an update fixed a trans issue I was having for more than a very short time period. The issue(s) I've had ALL required mechanical repairs. Most times, dealers agree but they are mandated by FoMoCo to do updates first.
 



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