- Moderator
- #1
nobodyspecial
Fire in the hole...
A little info first, my Expedition is a 99 5.4L with the A4wd, 4HI, and 4LO transfer case, unsure which model case it is.
Here is what I experienced today. While under any acceleration at highway speeds on dry pavement, I felt a vibration on my feet, coming from the front end.
I stopped, pulled the fuse for the A4wd clutch system, giving myself only rear wheel drive, all the time, and the vibration completely vanished.
I was under the impression that in the A4wd setting, the transfer case is in 2wd, but when any slippage is detected, it shifts into 4HI until no longer needed. If I am incorrect in my knowledge of the system, please let me know.
I would not have thought that the front axle would be engaging in these conditions.
Now that I have figured out where the vibration is coming from, where should I go from here? There is not a single leak on the bottom of this truck, everything is completely dry and clean, which I am surprised at, considering its 120k miles.
Here is what I experienced today. While under any acceleration at highway speeds on dry pavement, I felt a vibration on my feet, coming from the front end.
I stopped, pulled the fuse for the A4wd clutch system, giving myself only rear wheel drive, all the time, and the vibration completely vanished.
I was under the impression that in the A4wd setting, the transfer case is in 2wd, but when any slippage is detected, it shifts into 4HI until no longer needed. If I am incorrect in my knowledge of the system, please let me know.
I would not have thought that the front axle would be engaging in these conditions.
Now that I have figured out where the vibration is coming from, where should I go from here? There is not a single leak on the bottom of this truck, everything is completely dry and clean, which I am surprised at, considering its 120k miles.