guzzon
Member
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.
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.