I'm curious...

I have an 08 SD with automatic hubs. They look like they are manual but are not. I've always had manual hubs on my 4x4's. Is there a way to change over the automatics to manual? Would this help increase the mileage on the 6.4?

 

the auto hubs are in free position when 4wd is not in use. with auto the computer locks them in which take a few feet of travel, or if applied while sitting still you will feel a small pop when you start moving. as far as mpg go's i dout you will gain anything other than an more empty space in your wallet. my truck has both manual and auto locking systems. the advantage of the manual lock is when you shift into 4x4 with the man. already locked in there is no delay time. when driving in snow i keep the hubs locked for quick reaction when i get to a spot thats in rough shape.

 

So, even though the hubs are in the locked position on an automatic hub, the hubs are not turning?

I did notice the brief delay when engaging 4WD.

 

They are manual and automatic both. You can turn them to lock manually or use the **** on the dash to lock them with vacuum. Either way you use the **** to engage the transfer case.
jr

 

if my hubs are not locked with the manual lockers. they are free till i shift into 4x4. one of my front hubs has a squeek in it and as long as i have the manual locks in free position and in 2wd i dont hear a thing. if i lock the hubs and stay in 2wd the squeek appears. with the hubs in the free position and i push the 4wd button it take about 20ft of travel then the squeek will appear and i know then that the computer has locked the hubs in with the auto feature. when i go back to 2wd it takes about half mile for the hubs to unlock and the squeek to go away. p.s. ford shop has checked out my hubs twice and cant find a reason for the noise. thankfully the noise is how i know that with the auto locks when in 2wd they are not locked. but if you have the manual locks on your hubs they should be functual. mine are.

 

In the auto position with the switch in 2wd...or the manual hubs in the "free" position the front drive line is not turning.

 

Superdutysquirrel you might check your u-joints/cv joints whatever you want to call them, the squeak is how I knew they were bad on my 03 dodge. If they start clicking you can be certain you have a bad joint.