I had to say how reliable things were the other day...

[Aspen03]

We were on our way down to Tennessee for the weekend and about 100mi in I heard/felt what was like a louder, more intense rumble strip for a few seconds, I slowed from highway speeds to about 30mph while quickly heading over a few lanes to the shoulder and the sound was gone as fast as it came. I kept a 45mph pace with flashers on for a couple miles with no apparent issues until I could pull off without fear of being ran into by traffic.

I crawled under the driver front where the sound appeared to be coming from and see a bit of oil/grease coming from the axle where it meets the diff. Just a thin coating with a little sling on nearby areas. When I last arrived everything in mid July there were no signs of leaks or residue anywhere under the vehicle.

The sound never returned, and after traveling some slow surface road for awhile I got back to the highway and made another 110mi without issue. I'm assuming whatever it was, completely failed inside the axle/hub. There are 0 apparent driveability issues. Am I safe to return home in a few days assuming nothing changes? Not a lot of options as far as shops are concerned in the area by the marina, on a holiday weekend at that. If it is an emergency family friends own the place and would likely extend access to their workshop if need be.

Nothing has indicated as a problem prior to this, the only thing of any mention was a slight vibration from time to time I could feel in the wheel, but I attributed that to road surface as it would come and go depending on the highway I was on. It did seem to be pretty much non existent now though, so I may have been wrong and this sudden failure may have been the result.

This is the first 4wd, and truck based vehicle I've owned so I'm not quite as up to speed as my prior vehicles. I have replaced axles in FWD vehicles before but I've never experienced an internal failure like this and still be able to operate. I didn't attempt to switch into any of the 4wd modes as I wasn't sure if it had anything to do with the noise I heard and didn't want to press my luck with something engaging and getting stuck.

This is a 2003 Eddie Bauer 5.4 4WD with HD Tow. No mods whatsoever aside from electronic goodies, stock wheels, tire size, etc. Any insight is greatly appreciated. I took several pictures and a video so I can compare to see if any additional leak occurs and threw a piece of cardboard under the wheel to catch any significant drips so I can see how severe it is compared to this evening. I'm not expecting much of anything but more info is better than none if so.

 

[Hamfisted]

Fluid level Ok in the front differential ? You'd probably have to put it up on a lift and run it through a few 4wd cycles to see if you can get the noise to repeat. But that front axle would certainly be suspect. They're not too expensive from Rock Auto, just labor intensive to replace (like everything else...). Possibly just that joint there getting ready to go. Are you near a shop down there that can take a look at it? Jack it up on that side and see if you see excessive play in that axle.


https://www.rockauto.com/en/catalog/ford,2003,expedition,5.4l+v8,1411119,drivetrain,cv+axle,2288

 

[Aspen03]

Nearby shops, as far as I can tell are closed aside from people that run a shop out of a home garage. We're down at Dale Hollow lake, the area around it closes up and heads to bed at 5pm it would seem. Gas stations are locked up tight before the sun sets...crazy.

I can get it jacked up in the repair shop of the marina most likely and check for play, later today though. I'll take a peek this evening before dinner, the kids want to get out on the water. I haven't checked the fluid in the diff, I had no tools on me...they were in a vehicle about a half hour behind us and the noise had gone away and drove fine so I didn't have them stop.

I'm not too worried about the cost, I essentially planned on dropping $1k a year minimum into this thing and 18 months after purchase I've spent $400 outside of oil and gas. Funds are ready for what it needs.

 

[TomB985]

I was going to reply earlier, but it’s been a busy day.

I haven’t spent much time on this form, but over the years the “rumble” noise in 2WD is a hallmark of an IWE actuator engaging when it shouldn’t. Usually because a vacuum leak in the system allows the spring in the hub to engage the splines when you’re going down the road.

The IWEs are the vacuum-actuated hub lockouts that disconnect your wheels from the axle shafts on the front axle. The default to locked without vacuum, and get “sucked in“ when the engine is started and the truck is in 2WD.