i have a 99 f-250 laright with the 5.4L can anyone tell me weather or not the fornt drive shaft should be turning while i wam in 2 wheel drive, the hubs are unlocked yet they do have auto if that makes a differance i dont know but everything keeps spinning in the front except the tires in 2wd is this suposed to do this cause it just started making a real bad chattering noise that comes and goes, please any comments would be greatly appreciated this is starting to irritate me greatly

 

In 2 WD drive , there should be nothing turning , Is it the drive shaft going to the front axle thats turning , or the small axle shaft from the diff to the wheel thats turning ??

If the small axle shaft on the back side of the wheel , I would say your AUTO hub has failed an is locked in , its a very common problem after a brake service if someone is not familar with 4X4 to mess up the hubs.

Sometimes you can get lucky if the auto hub isnt damaged , just bound up , remove it , an re install it , Theres a procudre to unlock the hubs if you back up like 20 feet an then pull foward like 20 feet an then go in reverse another 20 feet. You get whats called axle wind up, an this should un wrap it if thats the problem.

Auto hubs are nice but rarely last very long, Manuel locking hubs are the best way to go, plus you can rebuild them, An on the trail its very easy to mechanial lock or unlock them if they fail .

If its the main shaft going to the front axle thats turning then you have xfer problems. If you have the auto shift feature on your truck for 4X4 it might be the elec motor has hung up very common problem . Or internal the shift dog has failed, or bound up., Let us know what you find