I washed my truck today, and as I was drying it off, I locked and unlocked the front hubs. Upon doing so I noticed bubbles coming from the center of the hub where it says "FORD" (on the ****). Is this where the vacuum bleeds off or something? Any info would be greatly appreciated. So strange looking, if you haven't seen it before, try it for yourself.

 

Vacuum leak shouldn't make bubbles.. it would ingest the water..

 

It's likely just regular wind or air movement and your hub gap is the perfect bubble wand.

 

It does this on both hubs, the grey FORD letters in the hub ****. Engine off, lock hubs and unlock them, with some soapy water on the FORD letters, it spits out bubbles right after its unlocked, neighbor saw it too.

 

The hubs jump out when they're released. And pull in when they're applied IIRC. Just the hub movin' around and pushing air I guess?

Kind of a weird fetish, but whatever works for you two. Just don't let any Dodge guys see it.

 

I can also hear the air hissing out from the same location.

 

Its not a vacuum leak.

 

Perfectly normal, there is absolutely nothing to worry about.

 

So what is the cause/source? I realize the vacuum supply to the hubs is for auto function, but how and why does it "vent" out through the center ****?

 

 

Makes sense, just seemed weird when I first saw it. Thought maybe it had something to do with my hubs being hard to rotate.

 

 

They're pretty hard to turn, I some times use a tool of some kind to assist, fingers alone won't do it. I plan on seeing the dealer in regards, and perhaps buy a pair of WARN hubs.

 

It takes some strength. It's not exactly comfortable on my fingers on either truck.

You'll lose the ESOF capability with the Warns, I think.

 

If the hubs are difficult to the point of being uncomfortable on your fingers to turn, something is wrong. Also, if you are seeing air bubbles coming out, that means water can get in, which means it probably has, which brings me back to my first statement; something is wrong.

There is an O-Ring that seals the locking assembly in place, this is supposed to be a vacuum tight seal, air should not pass it. The other point of ingress for water/contaminants is the vacuum hose on the back side of the hub assembly. It comes in the top, and the hose will often dry rot and split after several years. This causes intermittent failure to function for the vacuum operated assembly, and will also allow water directly into the locking assembly.

Ford offers a rebuild kit which includes the replacement O-Rings, but there is a fair chance that you are past that point if the hub is that difficult to turn. A small child can turn the locking mechanism; it should be very easy. Regular service of these hubs is advisable to prevent them from being damaged beyond repair; new ones are not cheap.

Regarding the Warn replacement version, they do not utilize the vacuum function. A cap is included with the kit to block off the port on the hub assembly after removing the vacuum hose. However, simply leaving the hubs locked during inclement weather still allows the ESOF to function, the only difference being the fact that your front axle is live all the time, and when you hit the switch it engages the transfer case.