Lost Overdrive?
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Freshman User
Joined: May 2019
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Unstick?
One very educated guess is that I have a stuck 3-4 shift valve.
Other thoughts?
Concurrence?
If you agree, what steps are necessary to unstick it?
My guess it that these steps, unless they include rapping on the tranny with a soft hammer, are outside of my skill set and tools.
Thanks.
Other thoughts?
Concurrence?
If you agree, what steps are necessary to unstick it?
My guess it that these steps, unless they include rapping on the tranny with a soft hammer, are outside of my skill set and tools.
Thanks.
Frmr Ford Trans Engr
Joined: Aug 1999
Posts: 24,698
Likes: 2,620
From: SE Florida
Unfortunately, that is all useless information. That is what the PCM has commanded the transmission to do. Of course it's going to be right.
You need to look at data from the sensors that actually measure the gear ratio of the transmission in real time.
You need to look at data from the sensors that actually measure the gear ratio of the transmission in real time.
Frmr Ford Trans Engr
Joined: Aug 1999
Posts: 24,698
Likes: 2,620
From: SE Florida
Turbine speed and output speed sensors. The PCM calculates gear ratio from these two sensors in real time. As I said above you can read the actual gear ratio by looking at a parameter called gearrat. Or gear_rat. I forget which way it's spelled.
Frmr Ford Trans Engr
Joined: Aug 1999
Posts: 24,698
Likes: 2,620
From: SE Florida
That looks like the data is showing the commanded gear, which is what the PCM is telling the transmission to do, What parameter is this showing?
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Freshman User
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Added Data
Maybe this is what you are looking for:
FORscan data 10.7.2019
I added to your previously requested gear ratio what appears to be an actual calculated trans ratio.
While the demanded gear ratio and calculated trans ratio roughly agree through third gear, you will see above that the calculated ratio does not match the demanded gear ratio once the PCM calls for 4th gear. Road speed was approximately 45 mph.
......Which is what my assometer has been saying all along.....my Ex is not shifting into 4th gear/overdrive, regardless of the actual road speed.
If, in fact, I have a stuck 3/4 shift valve, I'd prefer to replace the entire valve assembly given the mileage of the vehicle.
Any recommendations? Stock Ford? Something not-too-radical from one of the top tuners like BTS?
Other thoughts?
Thanks!
FORscan data 10.7.2019
I added to your previously requested gear ratio what appears to be an actual calculated trans ratio.
While the demanded gear ratio and calculated trans ratio roughly agree through third gear, you will see above that the calculated ratio does not match the demanded gear ratio once the PCM calls for 4th gear. Road speed was approximately 45 mph.
......Which is what my assometer has been saying all along.....my Ex is not shifting into 4th gear/overdrive, regardless of the actual road speed.
If, in fact, I have a stuck 3/4 shift valve, I'd prefer to replace the entire valve assembly given the mileage of the vehicle.
Any recommendations? Stock Ford? Something not-too-radical from one of the top tuners like BTS?
Other thoughts?
Thanks!
Frmr Ford Trans Engr
Joined: Aug 1999
Posts: 24,698
Likes: 2,620
From: SE Florida
Yes, that's what I was looking for. That does confirm that while it is commanding fourth gear it is not achieving it. You'de be surprised how many people tell me they don't have fourth gear and the problem is really that the torque converter isn't locking.
I don't know anything about aftermarket valve bodies.
I don't know anything about aftermarket valve bodies.
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Freshman User
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Off to Dealer
Thanks for your analysis and assistance.
Off to the dealer tomorrow am.
I will share data and outcome.
Brian from BTS recommends fixing the stuck 3-4 shifter in order to retain the original valve body.
I will report back.
Off to the dealer tomorrow am.
I will share data and outcome.
Brian from BTS recommends fixing the stuck 3-4 shifter in order to retain the original valve body.
I will report back.
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Freshman User
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No Go at Ford Dealer
My local Ford dealer does not want to get into the shifter valves. They did see the same code, but have experiential data from Ford that this can veer off into overdrive clutches and solenoids. And, 50% or so of Ford reported fixes for this code were simply full tranny replacements.
I respect their hesitancy.
I will visit a recommended local tranny guy tomorrow who is happy to drop the upper and lower valve bodies as a unit and take a look see at the 3-4 shift valve.
Bonus points that they build up trannies for chipped 7.3s and are aware of Brian at BTS and his products.
Update to come in a day or so.
I respect their hesitancy.
I will visit a recommended local tranny guy tomorrow who is happy to drop the upper and lower valve bodies as a unit and take a look see at the 3-4 shift valve.
Bonus points that they build up trannies for chipped 7.3s and are aware of Brian at BTS and his products.
Update to come in a day or so.
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Freshman User
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Fixed
As suspected, stuck 3-4 shift valve.
Valve and body scored from use.
Smoothed and reinstalled.
The proof is here...45 mph or so:
FORscan Lite screengrab on Android 10.11.2019
The work was done byA-J & H Transmissions located in Palatine IL
www.a-jandhtransmissions.com/
I recommend them highly if you are in NW Il.
Particular thanks to Mark.
And also Stewart for (along with Mark) the FORscan recommendation. Cool tool with many other uses.
Hope this helps someone else.
Valve and body scored from use.
Smoothed and reinstalled.
The proof is here...45 mph or so:
FORscan Lite screengrab on Android 10.11.2019
The work was done byA-J & H Transmissions located in Palatine IL
www.a-jandhtransmissions.com/
I recommend them highly if you are in NW Il.
Particular thanks to Mark.
And also Stewart for (along with Mark) the FORscan recommendation. Cool tool with many other uses.
Hope this helps someone else.
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