Cosmos,
So for some detail, I have about 91K on the MKX. As for as far as environment, I am in the St Louis area, we get some snow, but really not that much as compared to up north.
As for the Brake line, it is the part number BRHF213 an what is happening there is a break in the hydraulic line under the shield that I circled in red. Each time it happened the mechanic reported brake fluid coming out from the end of that shield hose. The is nothing as far as leading events, fluid levels were normal, I have the dealer change my oil every time and the do a "21 point inspection" or something like that, so if there was tail tail signs I think they would have flagged it. When it happens it is all the sudden as I am driving and try to brake and then my foot goes all the way to the floor with a minimum of braking happening. The first time it happened I was on the freeway heading home from work going 60+ mph, liked to scared the **** out of me. But I was able to get the vehicle stopped, the second and third time is was in a parking lot going into a parking place, but I could tell immediately what was going on, and grabbed the e-brake as a back up. As for the temp, the first was in April (60+f), the second in June (70-80) and last Saturday is was in the 40's.
Oh what topped it off, yesterday after work as I was walking out to my vehicle I just happen to look down at on of my rear wheels (where lines were replaced) and here was one of my lug nuts half the way off. Stupid mechanic did not torque down any of the lug nuts in the rear, I am lucky they did not come off since I drive about 25 miles each way to and from work. So I had driven on the vehicle for 75 miles at least before I discovered the issue. I am going back to the shop and talk to the store manager.... A little ticked to say the least.