I have vibration somewhere in the driveline/drive train. It begins near 50mph and gradually goes away after 60mph. I have also noticed that when I turn the OD off, I no longer feel the transmission downshift, like it did 15K miles ago, I now have 38K miles.

The vibration is most noticeable when hold 58mph steady. Also when I pull a 12ft utility trailer, it feels like I have a low or flat tire somewhere behind me. I also took the trailer and had all the tires balanced and the mounting inspected, as it is less than a year old, there was nothing wrong with the trailer. The trailer pulled fine behind any other truck that I have tried.

I have taken it to the dealer, as of yet they don't know what's wrong, so I extended the warranty to 100K, just in case. They did remove a weight off the drive shaft and assured me that the lack of the weight was not the problem. I had the trans serviced and all maintenance is on time.

I had the same problem with my '92 E250 van. The trans was replaced twice, I replaced all the wheels and completely went through the front and rear suspension with the dealership. Let's not get started on the van....

Anyway does anyone out there have any idea why this vibration is there and is related to the loss of the downshift down-kick?

2006, F150 XLT, SuperCab, 4.6, EOD, 38K miles.


William

 

I have the same issue, except I have a 98 F150 long bed extended cab. My main problem is my driveshaft and carrier bearing. I have an appointment at a shop that deals with driveshafts next week. I'll tell you if it helps.

 

I'll see what the dealership has to say. Whe I had the prob with my '92 E250 van, We did almost everything, I got the feeling that it was either in the engine, lower end or somewhere around there. The prob becomes more noticible when towing. So that may be a clue.

Thanx Bill