What is this plug on my axle housing? 2 wire, I think it's a dana 80
96 f superduty, drw

 

460 gas engine

 

That is the Vehicle Speed Sensor (VSS). It provides a signal for the Rear Anti-lock Brake System (RABS). Then the signal is buffered (PSOM behind the speed/odometer) to provide vehicle speed feedback for the speedometer/odometer, speed control and Powertrain Control Module (PCM aka computer).

 

Not being snarkey, but how long was this thing on the bottom of the lake? I mean, for a '96,

 

Right, was a salt truck

 

Ah, the further North you go with bigger/big cities, the more salt is used so people can continue life. Decades ago I moved way south to the land of no salt. SO much nicer not fighting rusted fasteners that break, being careful that rust doesn't fall into my eyes, etc. And the feeling that my repair work may not be worth it, as rust ate everything away. Parts used to literally fall off of cars due to rust. Worked with guys in the 1970's that lost a door, a gas tank(!) while driving!

There was an age-range of Ford/Lincoln/Mercury that dropped their big rear 5 MPH bumpers off on the road, drivers didn't realize they dropped it.
I (barely!) missed one on a rural interstate as I changed lanes in a bad fog. I checked over my shoulder again as I went from left lane to right, wife said "watch out!!!!", I looked forward quick, just a quick glimpse of it out of the fog, swerved back by inches. It blended in well with the road. Would have been devastating driving a FWD car we had that time. And no, I could not ID what model/year it came from

 

I believe when it comes time for that sensor to be replaced, new words are gonna be added to the adult's only section. Whatever ya end up doing, Don't use a hammer on that rear.