Mysterious Vibration......
#1
Mysterious Vibration......
So I'll keep this short and sweet...
2010 F150 STX 4.6 2V 4spd Auto 4x4 175k on the ticker...
Truck has generated a vibration that starts at 35mph and continues until your going fast enough that it goes away. At any point you can take your foot off the throttle and the vibration stops, just the slightest amount of load on the drive train will bring it back. It doesn't matter how you drive it or what gear your in it does it like clockwork starting at 35mph. I have also taken the rear drive shaft out and driven it in 4wd and there is no vibration at all, put it back in and it comes back. I will now list all the things checked on the truck so far as I have no idea where to turn at this point. I have read countless threads but can't seem to find anything pointing to a solution. Any help would be greatly appreciated.
New spark plugs
New coil packs
New U Joints
Rear diff was serviced 5000miles prior to problem and everything looked great in there.
Spent 3 days at a transmission shop and they are quite confident it's not in the transmission but not ruled out yet.
Spent 1 week at a mechanical shop getting the motor checked out for any possible misfires or other issues and found nothing.
Pulled the rear drive shaft and had it checked for trueness and balance.
Tires have been road force balanced, rotated and changed out for another set.
I don't know where else to look...the fact that it doesn't do it when the rear drive shaft is out rules out motor and transmission issues to me. Is it possible the transfer case could be the culprit?
Thanks!
2010 F150 STX 4.6 2V 4spd Auto 4x4 175k on the ticker...
Truck has generated a vibration that starts at 35mph and continues until your going fast enough that it goes away. At any point you can take your foot off the throttle and the vibration stops, just the slightest amount of load on the drive train will bring it back. It doesn't matter how you drive it or what gear your in it does it like clockwork starting at 35mph. I have also taken the rear drive shaft out and driven it in 4wd and there is no vibration at all, put it back in and it comes back. I will now list all the things checked on the truck so far as I have no idea where to turn at this point. I have read countless threads but can't seem to find anything pointing to a solution. Any help would be greatly appreciated.
New spark plugs
New coil packs
New U Joints
Rear diff was serviced 5000miles prior to problem and everything looked great in there.
Spent 3 days at a transmission shop and they are quite confident it's not in the transmission but not ruled out yet.
Spent 1 week at a mechanical shop getting the motor checked out for any possible misfires or other issues and found nothing.
Pulled the rear drive shaft and had it checked for trueness and balance.
Tires have been road force balanced, rotated and changed out for another set.
I don't know where else to look...the fact that it doesn't do it when the rear drive shaft is out rules out motor and transmission issues to me. Is it possible the transfer case could be the culprit?
Thanks!
#2
Okie Coupe
iTrader: (1)
I would bet on the drive shaft. It could be a number of things causing the vibration. Carrier bearing, wheels and or tires, something loose in the suspension or even a motor mount to name a few. It's possible it could be a combination of things on a truck with 175,000 miles.
Don't become a parts changer to find what the the problem is.
Don't become a parts changer to find what the the problem is.
Last edited by shortride; 07-05-2015 at 09:30 AM.