Shuddering hesitation

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guzzon

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I have a 2017 4wd with the 3.5 ecoboost. Your description matches pretty closely an issue I was seeing about a year and a half ago. I took it to the dealership and initially they thought it was a faulty front diff actuator solenoid - basically it was trying to engage the 4wd intermittently. They replaced the solenoid but that didn't solve the problem.

It wasn't until I had one of their mechanics jump in the car with me that they understood exactly what I was talking about - for me it was similar to what you described - when adding a little on the accelerator, particularly at freeway speeds it felt almost like hitting a rumble strip.

They had a lot of trouble de-bugging it but in the end it came down to a sensor integrated into the molded lead frame (TBH I don't know the details of what sensor). They replaced the lead frame and the problem went away. I also noticed a 2-3 mpg improvement in gas mileage after this repair.
 

DCowan

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I had same problem a few weeks ago with my '15 Exp...it was bad plugs (which they replaced for free since the plugs were replaced by Ford only 8 months ago) and a couple problem coils. Easy fix.
 
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sduncan000

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Just to bring up to date - yeah, it is the 3.5, not the 3.7 (my bad!), and I added the 'Instant Shudder Fix'.
I had to siphon out a couple of ounces of fluid as it was fully topped off, but then added the Shudder fix and it worked just as it is named - instant relief.
I think I will likely go back in and replace the filter and do a full fluid change, but I hope that will wait until spring.
Time will tell.
Thank you to all for the advice and ideas
 

Motorcity muscle

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Not sure shutter fix is a good plan, most trans tech's do not recommend it, just like engine oil additives.
 

hapEcat

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Our 2017 EL Limited has been exhibiting the shudders like you describe, but when this happens the Tach will increase 100-200rpm, then settle back. It's like a sensor can't make up it's mind as to what gear it wants to be in, or whether the Converter should be locked or unlocked. Watch your Tach.
 

poorboy08

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I have a 2017 4wd with the 3.5 ecoboost. Your description matches pretty closely an issue I was seeing about a year and a half ago. I took it to the dealership and initially they thought it was a faulty front diff actuator solenoid - basically it was trying to engage the 4wd intermittently. They replaced the solenoid but that didn't solve the problem.

It wasn't until I had one of their mechanics jump in the car with me that they understood exactly what I was talking about - for me it was similar to what you described - when adding a little on the accelerator, particularly at freeway speeds it felt almost like hitting a rumble strip.

They had a lot of trouble de-bugging it but in the end it came down to a sensor integrated into the molded lead frame (TBH I don't know the details of what sensor). They replaced the lead frame and the problem went away. I also noticed a 2-3 mpg improvement in gas mileage after this repair.
Can you elaborate on "lead frame"? Your problem sounds exactly like the one I'm having, would be interested in more information about what sensor you would be referring to?
 

Steveooo

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I've been having the exact same issue. Usually while going up a slight incline while maintaining speed and right where a downshift would seem in order it shudders. Putting it into tow/haul mode resolves the issue.

I changed all plugs (was at 100k miles anyway) and the condition improved greatly but not completely. It still happens but not as "violently" as before the plug change.

I did check it on a scanner at an automotive store and no codes came up. I've also had no check engine lights so far.

Start changing coil packs next? Or try the Ford friction modifier?
 

The Swagonmaster

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I have a 2008 Expy 5.4, same issue. Turned out to be bad plugs. Ohm'd the coils and they were reading fine. Luckily none of the plugs broke as i was pulling em out but they were definitely fouled. Replaced em all and shudder went bye bye. Start easy before digging into the trans.
Absolutely correct, you can waste a boat load of money and a lot of time throwing parts at a problem, always better to at least try to diagnose the problem first. BTW, back years ago when I worked at a transmission shop I learned that one way to tell if the shudder was engine or trans is to hook up a vacuum gauge to engine vacuum and watch it when the shudder is happening. If the problem is in the engine the vacuum reading will fluctuate but if it is the trans there won't be any change.
 
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