Alight, first thing i'd be doing now was a can of non chlorinated brake cleaner and hosing that whole thing down, then keep an eye on it.

 

^^^^^This^^^^^
the leak looks like it is running down both the front and the back side of the housing, I doubt that it's the axle tube. I know it doesn't look like the sensor location is leaking but I'd bet, by the location of the wetness, it's that sensor location or something close to it, leaking and running down both sides.

 

I agree, and maybe its the rust that's right there, making it seem dry around it. That would, I hope be a much simpler explanation and hopefully easy fix...btw...what is that senor and what does it do?

 

Personally, I wouldn't worry about that, but cleaning it and continuing to watch is a good idea. If it does start to actually leak rather than seep, then the axle is likely not straight, so at that point you would have to decide if you want to try epoxy to stop the leak, or if the entire axle would need replacing. Welding steel tubes to cast housings takes extra pre/post heat to keep the welds from cracking, but as stated earlier you would need the entire housing to be removed from the vehicle and emptied of bearings, seals, gears, etc. in order to do that. I have a Jeep with aftermarket axles and I welded the tubes to the housing in that in order to not spin the tubes, but that was before the axles were installed, and that thing is only meant for getting beat on hard trails. I wouldn't bother welding on a purely on highway vehicle.

 

I wouldn't worry about it, I noticed the exact same thing on my 2017 at around 20K. I took it to the dealer "they inspected the case, checked fluid level" and told me to drive it. Im at 55K and it is now completely dry, so it either sealed up or it has no fluid left.....

 

 

Guessing someone picked up the rear of your truck with a floor jack by the pumpkin.

 

 

Pardon the ignorant question, but how would this result in a leak from the tube to casting joint?

Also minor correction to comments above: the connector is not a sensor. It is power for the electronic locker in the rear diff.

 

Because it's not designed to be used that way.
A lot of stress applied to those connections if you do.
The owners manual states pretty clearly not to.