Ford f-350 front end vibration

[BILBO913]

i know on mr we got a couple of gear heads so im looking for alittle help, im working on a 08 f350 diesel, manual locking 4X4 hubs, dana front axle. at 40 mph with the hubs locked, but transfer case not in 4 wheel the truck gets a wicked vibration. ive replaced both front axle u-joint. didnt fix the problem.then i locked the left hub and left the right in the free position,the vibration went away. then locked the right and left the left free, the vibration came back. so i replaced the right 4wd hub and still have the vibration. im going nuts. i think its something internal in the front diff. but later just for good messure im gonna pull the front drive shaft from t case to front diff.

any help would be great

 

[mbg75]

Probably not the driveshaft. The front axle is usually not limited slip so when u only lock 1 hub, the diff don't spin together..
I get a slight vibration on mine with the hubs locked also. It goes away as soon as its in 4wd.

Sent from my ADR6300 using Tapatalk

 

[greg 45]

Did you get the bullitten from ford on tire pressure and vibration.
I have a 05 the tires are rated for 80 lbs thats what i keep in them .
When my front u jounts froze the truck stearing would lock and bind up.

 

[NYreefNoob]

start with the basics, pull tires and balance them, check for odd wear on tires, do you have any pulsation when braking also ?

do you get the vibration when it is in 4 wheel drive and hubs locked in ?

also why would you be driving with hubs locked in and not in 4 wheel drive

 

[motortrendz]

thats an odd one.. what type of diff is in the front axle? is it locking? going into basics, if its locking and you didnt add the propper additive lube it can cause a chatter or vibe when turning.. (i work for jeep not ford) also is this front dif a solid axle? or is it a short axle with CV shafts? check the suspension for loosness with it unloaded, and look at the tires, do they have funny wear on them like cupping or feathering?

 

[BILBO913]

this problem started back in october when we got that snow storm. the hubs stay locked most of the time because its a work truck it goes from job site to job site.tires have been replaced since the problem started.
motortrendz its a dana. yes the hubs lock and when you shift the transfer case into 4wd it engages. i also work for a chrysler dealer not ford. it is a solid front axle.it is time to do a driveline service. maybe the fluid is really beat. but i think its a bad bearing internaly in the diff it self

 

[motortrendz]

possibly the right side outer bearing is bad or the axle may be bent and u can only feel it when its engaged and not floating..

 

[NYreefNoob]

if used to haul or plow you should be doing the 4x4 service every 15k and yes if the diff fluids have never been changed it can cause a chatter and burn the gears out