4H always engage after truck starts

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Old-Raptor-guy

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@Old-Raptor-guy because I can monitor it on Forscan
That does not tell me what indication you have it is in 4x4.

There was something, a noise, a vibration, lack of power, poor fuel mileage. Something got your attention.

Although not impossible, I highly doubt you woke up one day and say "I wonder if my 4x4 is engaging by itself"

What led you to the point of using forscan to look at your 4x4 system.

i have been doing this a long long time, most probably dont know what SBDS is.

anyway i have learned to not trust scan tool data 100% (and i have IDS/FDRS)
 

TwizzleStix

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Here’s your codes. You need to jack up the front and do a manual check of each side IWE is engaging or not. With water damage and likely wiring problems, your ScanTool/FORScan tests are not reliable.


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Mylo2021

Mylo2021

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That does not tell me what indication you have it is in 4x4.

There was something, a noise, a vibration, lack of power, poor fuel mileage. Something got your attention.

Although not impossible, I highly doubt you woke up one day and say "I wonder if my 4x4 is engaging by itself"

What led you to the point of using forscan to look at your 4x4 system.

i have been doing this a long long time, most probably dont know what SBDS is.

anyway i have learned to not trust scan tool data 100% (and i have IDS/FDRS)
@Old-Raptor-guy I can tell that the 4x4 is engaged because is hard to turn and the tires squeal. Also when I start driving with the Forscan I noticed after 400 Seconds aprox the SIGNAL "YES" changes to "NO" and after that I turn the knob to 4H it will engages and the signal changes to "YES" and everything works fine until I turn off the truck.
 

FordTechOne

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@Old-Raptor-guy I can tell that the 4x4 is engaged because is hard to turn and the tires squeal. Also when I start driving with the Forscan I noticed after 400 Seconds aprox the SIGNAL "YES" changes to "NO" and after that I turn the knob to 4H it will engages and the signal changes to "YES" and everything works fine until I turn off the truck.
It sounds like your transfer case it mechanically stuck in 4WD. That’s why it binds up until the IWEs disengage after the initial start period.

If you jack up the front of the truck in 2WD you should be able to turn the wheels and front driveshaft by hand. If the front driveshaft won’t turn, that indicates it’s locked to the rear shaft due to the t-case being stuck in 4WD.
 
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Mylo2021

Mylo2021

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It sounds like your transfer case it mechanically stuck in 4WD. That’s why it binds up until the IWEs disengage after the initial start period.

If you jack up the front of the truck in 2WD you should be able to turn the wheels and front driveshaft by hand. If the front driveshaft won’t turn, that indicates it’s locked to the rear shaft due to the t-case being stuck in 4WD.
Thanks for your advice. I lifted the truck and tried to turn the front driveshafts by hand and they were locked. When my truck got flooded they dissembled the Transfer case and the transmission. I don´t know if is possible that the mechanics had ensembled in the 4x4 position. @FordTechOne I noticed that 4th gear is weird. when is shifting 4th to 5th it holds a little longer like it was slipping. that might be caused by water coming inside the transmission or I am being just superstitious. My truck got flooded when it had around 9600 miles, now it has 18000 miles.
 

FordTechOne

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Thanks for your advice. I lifted the truck and tried to turn the front driveshafts by hand and they were locked. When my truck got flooded they dissembled the Transfer case and the transmission. I don´t know if is possible that the mechanics had ensembled in the 4x4 position. @FordTechOne I noticed that 4th gear is weird. when is shifting 4th to 5th it holds a little longer like it was slipping. that might be caused by water coming inside the transmission or I am being just superstitious. My truck got flooded when it had around 9600 miles, now it has 18000 miles.
If water got inside the transmission, all of the clutch packs need to be replaced. The clutch material is held to the plates with a water based glue; it disintegrates if there is water contamination.

As far as the T-Case, it could be mechanically stuck in 4H, or the shift Motor could be stuck/failed. You can pull TCCM DTCs with ForScan to see if there’s a shift Motor related issue.
 
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Mylo2021

Mylo2021

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If water got inside the transmission, all of the clutch packs need to be replaced. The clutch material is held to the plates with a water based glue; it disintegrates if there is water contamination.

As far as the T-Case, it could be mechanically stuck in 4H, or the shift Motor could be stuck/failed. You can pull TCCM DTCs with ForScan to see if there’s a shift Motor related issue.
@FordTechOne no DTCs found
 

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FordTechOne

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Since there are no DTCs, that indicates the shift selector can move, but transfer case is mechanically stuck in 4WD. I would remove the shift motor as an initial inspection; the selector lever can be turned with a wrench. You should be able to feel the change between 2WD, 4WD, and 4WD Low.
 
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