Hard brake line replacement help

[M3GA]

Anyone replace their hard steel lines and have a DIY or guidance?

Both rears rusted at the junction between the hard line and rubber hose and leak. I repaired the passenger rear at the junction, but I failed today trying to flare the driver's rear. Will replace both rear lines, fronts too if in bad shape.

Bought two 5' copper brake lines, not sure what length lines I need. Advice on lengths for all four corners?

Also is there a midway junction that serves the rear vs replacing all the way to the master/pump?




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[FBloggs]

Why not get Genuine BMW?
from the dsc to rear there are two.
Then a third one to the right side rear.

[M3GA]

Why not get Genuine BMW?
from the dsc to rear there are two.
Then a third one to the right side rear.

OE steel lines seem much harder to install on jack stands, nickel copper lines can be easy bent into place.

What do you mean two lines to the rear and a third to rear right?

I found this pic on realoem, but not sure which one is correct. Maybe you're referring to the second pic? If so, seems I just need a short section to the intermediate junction vs replacing the whole line.



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[FBloggs]

Is your car pre 9/2002.
I looked at the middle diagram.
1,2, and 4?

[M3GA]

Is your car pre 9/2002.
I looked at the middle diagram.
1,2, and 4?

2003 (09/2002). I did more work on it today, and as far as I can tell (without removing any undercarriage parts) it is the 2nd diagram. I'll post an update with where I'm at.

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[M3GA]

Update:
Loosened up the rear connections, there is an intermediate junction (union) in the rear left wheel well that transfers over to the rear right hose/caliper. This was also rusted up, but with a little heat (15 secs) and PB blaster, it came loose.

The hose clamps over the rear subframe were a pain to unscrew, but doable without removing anything. Used a 13mm ratcheting wrench to slowly loosen plastic nut then pulled out the brake pipe.

I'll be replacing the rear transfer pipe from the junction to rear right. It's about 4 feet.

Also, there is just enough pipe coming out from the rear left post-fuel tank to add a union there. So will add about 6-8" curved pipe post-tank.

Ordered the ECS bubble flare tool and 25' nickel-copper piping with assorted fittings from Amazon.

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[FBloggs]

Best of luck.
I'm about to replace the main line to the rear on my E30 M3.
If it had been a non M, I would have spliced in a small section.