2007 F350, bad vibration around 70-80km/hr, it is like 4X4 is engaged. removed both lock hubs and marked both axle shafts and front drive shaft with paint marker. Drove truck and kept checking if marks moved, all good up to 60km/hr, but at 80 vibrating, marks on shafts moved. As if I was in 4X4, turn selector switch alot of times, still does it. With both hubs removed and in 2wh drive the shafts should not move. The T/C motor clicks when I engage 4wh drive every time. Any ideas. Thanks.

 

Never heard of this so..Bump to the top to try and find an answer

 

I found the rear joint worn at the rear diff. should be the cause of the vibration, but you would not think that the front shaft would rotate when both hubs are removed.

 

how much did they move?

an honest guess here but I was thinking its possible with the normal vibration and road conditions they would just "naturally" move slightly, and with the vibration issues causing the "natural" movement to increase. I'll check this on my truck, Ill be on a pretty bumpy highway tomorrow for about 100+ miles. Ill report on it tomorrow.

 

changed out u-joints and vib is now gone. Still don't know why front shaft moves.

 

Probably just oil drag in the t-case.