I own an '09 f-350, Crew w/4WD - the truck has 48,000 miles.
I had the EXACT same thing happen to me last week. The hubs were in auto and I am on the highway doing about 65 mph when there was an explosion under my truck. My truck was towed to Roosevelt, UT & to Palmer Mechical & Tire, which is a large repair shop in oil field country. The owner and the chief mechanic remarked that the incident was not uncommon. They confirmed that the hubs were in "Auto" BUT were not disengaged. They said that most of the transfer case failures they had seen were on vehicles with 100,000 miles or more and most occurred when the hubs did not disengage or when the universal joints failed.

 

ya'll just made me go out and make sure mine are disengaged.

 

Sat down with the service manager at Lithia Ford in Boise ID
He said that he had seen the problem but only once. In checking around - it looks as if we must either switch out the hubs for manual ones or get under the the truck to ascertain that the Auto huds are actually dis engaged. What a crock?!?!?!?

 

The crock is believing everything you hear. There are tens of thousands of trucks that run with hubs that are manually locked, and they don't blow up their transfer cases. Unless there is something else seriously wrong, locked hubs can't hurt the transfer case.

If you have seized U-joints in the front driveshaft it certainly could. But that would happen when you engaged 4WD even if your hubs weren't locked in.

 

I agree with you here. You want to be in 2wd drive only and if you are locked in the pavement better not be dry.

 

I have seen the same damage from a previous post. I don't remember what was the cause of that failure. I think that your problem was that the transmission did not shift out of 4wd and that caused the failure.

 

Yes. That is indeed what happened. The loose spinning (half) drive shaft broke a lot of things. It broke a fuel line off of the fuel pump. It broke off the transfer case shift motor. It bent the front left sway bar at the upper bolt.
There are bangs and dings all over the place.

 

Right now, without the front drive shaft, if I try to turn the the front differential where the drive shaft connected to, I can only turn it a very small amount back and forth. I can see that the front differential is trying to turn the connections to the front wheels (sorry I don't know the technical term for this). So this seems like my front hubs might be engaged even though they are in Auto. The other end on the new transfer case spins freely.

I also have a 2002 F-350 DRW 4WD 7.3L and I can't turn the front drive shaft on this either when the hubs are in Auto. Do I have a second vehicle with bad hubs?

Can others confirm that they can spin their front drive shaft freely by hand when in 2WD?

BTW, driving home without the front drive shaft, I noticed my gas mileage shot up significantly! I was getting above 18 mpg which I have never seen before with this truck. Typical gas mileage before was 13 mpg unloaded. Is this an indication that my front hubs were locked?

 

So this would be a problem within my old transfer case itself?
What causes this? Does a bad transfer case shift motor do this?

If the transfer case is stuck in 4WD but my hubs are not locked would this still cause the problem?

I would think that if the hubs were locked and the transfer case was in 4WD that the driver would have figured out within a few turns before getting on the freeway that 4WD was engaged.

 

Yes I can turn my front drive shaft freely when in 2WD and the manual hubs are unlocked. Of course lock the hubs and it won't turn when in 2WD. I drive it like this once in awhile to "lubricate the front end"
('02 f250 5.4 with manual trans)

 

All of my trucks have had the hubs locked in virtually full-time their entire lives I've owned them (signature for details on them, 4wd almost every day) and have driven everyone of them on dry pavement in four-wheel-drive at high-speed in the winter and haven't exploded the transfer case yet. But all have needed u joint replacements for the front driveshaft at some point... If driven with a front driveshaft vibration serious enough it will split the transfer case in half, I honestly think with the noise (squeak in your description) from your rebuilt driveshaft it was possibly the culprit.

 

<p>Agree with Andy. &nbsp;There are a LOT of people who keep their hubs locked in, and a lot more who have used 4WD on dry pavement from time to time. &nbsp;It's relatively rare to blow up a transfer case, I blame the U-joints as well. &nbsp;</p>

 

Or the centering ball in the CV U-joint, it can literally launch the driveshaft out from under the truck when it fails at high-speed.

 

Here is a photo from an excursion I just got.

When I picked it up both front hubs were in auto, and selector was in 2wd. Both lock outs were locked and I tapped them with a rubber mallet and they both popped out of lock configuration.

Drivers tire was noticeably low probably 20 psi different than passenger side. In my situation I am leaning toward the low pressure in the front left tire causing this transfer case blow out.

In my case I tend to like the factory hubs....I picked up this 2000 4X4 V10 Limited EX with 210,000 miles for $1760 delivered to my driveway. All because of a low tire and sticky hubs.

A few hours labor, $125 + $35 core for a used transfer case from local pick and pull, a new front drive shaft and it will be a good running Ex again.