In cases like that (and I've dealt with this on a regular basis for the last 35 years) I would tell the customer we're doing it all, or not doing it at all. Change one blown line while the others are ready to blow, you're leaving yourself open to all sorts of legal bull****...... there's far too many ambulance chasing lawyers that would love to have a shot at that one.
This was my neighbors friend. I did it in my driveway. I was not working as a mechanic in a shop. I did tell her I could do a whole system to make it road worthy but she just wanted something fast and cheap. I told her I did not want to be responsible for her having an accident. I refused her after that. I always get someone trying to get something done on the cheap. I just tell them sorry I don't have time. I have my own stuff that I have to take care of.
I was doing a favor for a friend who needed a brake line replaced ages ago. I take a peak and find compression fitting after compression fitting. Some weeping, some connected to a couple inches on rusted brake line into another fitting. I offered to help him replace the lines but he wanted a quick fix. I said yea..no
I was thinking that the other day. Aluminum gets a film of corrosion on the outside that stop further corrosion. That's why British cars have so much electrical trouble. It's softer and I've seen sides peeled off when they sideswipe something. I think the hardware (bolts) and parts that have to be steel (brake lines) will be the weak point. 20 years from now, we may see older equipment where the bodies fall off.
I don't believe the rust is going to be the bigger issue. The problem with ford is the same has always been, poorly engendered ugly junk,
I thought it was amusing that last week it was repairing a dent on the bedside of an F150 and took taillight out for access and the inside was rustproofed from the local guy who mechanics and body guys have been mf-ing for 30 years... I guess he’s got a special aluminum formula.... or a great sales pitch.
it won't matter....NOTHING lasts more than 10 winters my buddy just did rocker panels & cab corners on his 2008 Silverado...the rust here is REALLY bad
10 year old truck, not surprised. I cringe when I get a work order for anything older than 2012 or so...... first step in most repairs is to wheel the torch over...