DIY: 2006 BMW E53 X5 3.0i Brake Line Replacement

[2004bmwx53i]

Originally Posted by andrewwynn

I bought a tool similar to the one you are using hurt it was unusable until I sanded down the mating surfaces and cleaned up the threaded parts.

Lubrication is needed on the flare surface when doing steel but I was able to make fine flares on steel even though I didn't need to I replaced both of the rear main lines.

Did you buy steel line or are you trying to splice into factory line (I do not recommend).

This is an existing line I busted during unsuccessful undoing of the rusted nut. I hate the thought of having to bend a new line, as I'm pretty sure it'll be a mess!
I really have to make this work. But first I must get it right on a test piece.
What is the reason that you don't recommend repairing the line?

[Calipsoe]

You might want to switch over to nicopp line. It's much easier to bend and flare. I've replace both rear lines with continuous runs of nicopp. The best part is it will never rust out again.



Bulk:

https://www.amazon.com/Nickel-Copper.../dp/B00A02C9H0


Or by the piece:
https://www.jegs.com/p/JEGS/JEGS-NiC...11534/10002/-1

[andrewwynn]

Originally Posted by 2004bmwx53i

This is an existing line I busted during unsuccessful undoing of the rusted nut. I hate the thought of having to bend a new line, as I'm pretty sure it'll be a mess!
I really have to make this work. But first I must get it right on a test piece.
What is the reason that you don't recommend repairing the line?

Experience. Old steel line almost always has more rust than you think.

I have had some success spkicing into old line but it's too risky if I can get to the ends of the full line I will always replace the whole line.

I did both my rear e53 lines with nicop and it was a breeze to clone the old "made of rust" steel lines by putting the old line in the 1/4" slot of the bender and the new line in the 3/16 slot. Taping the new to the old as I went. Made a perfect copy.

It's also at least 4x as difficult to make the flare on steel and that's actually the biggest problem on old lines. About 30-50% of the time the steel would split at the flare because it lost ductility.

It's a little tricky getting the full line out and in you have to temporarily add and subtract an extra bend if your axle is installed but totally doable.

The union to the right rear wheel is basically impossible to access without a crow foot socket but 4/10 difficulty with one (or Two: one to hold the back side).

I think I did a write up when I did mine but may have just posted on somebody else's thread

[andrewwynn]

https://xoutpost.com/bmw-sav-forums/...placement.html

See my post #4 I have a link to icloud photo album showing how I cloned an old line.

[2004bmwx53i]

Originally Posted by andrewwynn

Experience. Old steel line almost always has more rust than you think.

I have had some success spkicing into old line but it's too risky if I can get to the ends of the full line I will always replace the whole line.

I did both my rear e53 lines with nicop and it was a breeze to clone the old "made of rust" steel lines by putting the old line in the 1/4" slot of the bender and the new line in the 3/16 slot. Taping the new to the old as I went. Made a perfect copy.

It's also at least 4x as difficult to make the flare on steel and that's actually the biggest problem on old lines. About 30-50% of the time the steel would split at the flare because it lost ductility.

It's a little tricky getting the full line out and in you have to temporarily add and subtract an extra bend if your axle is installed but totally doable.

The union to the right rear wheel is basically impossible to access without a crow foot socket but 4/10 difficulty with one (or Two: one to hold the back side).

I think I did a write up when I did mine but may have just posted on somebody else's thread

Appreciate your thoughts. Thanks

[StephenVA]

+1 on "e53 lines with nicop". The steel lines are compromised and the patch and repair process will have you redoing the entire rear lines within two years.

[2004bmwx53i]

Originally Posted by StephenVA

+1 on "e53 lines with nicop". The steel lines are compromised and the patch and repair process will have you redoing the entire rear lines within two years.

If steel lines are that bad, why BMW uses it. Mind you, this line that I took out due to rusted connection nut to the end of the brake hose, was in perfect condition along the rest of the line. I had to use dremel grinder to scrape it off. This is after 18 years of salty road exposure. The weakest point seems to the nuts and not the steel line.

[StephenVA]

If your lines are NOT having coating peelings, corrosion flaking, and leaking lines, count your blessings.

See this post for examples:
https://xoutpost.com/bmw-sav-forums/...ine-check.html

[2004bmwx53i]

[QUOTE=StephenVA;1217572]If your lines are NOT having coating peelings, corrosion flaking, and leaking lines, count your blessings.

I've had more than my share of brake line problems in the past though, the same as mentioned in the link.

Safe driving everyone

[andrewwynn]

Originally Posted by 2004bmwx53i

If steel lines are that bad, why BMW uses it. Mind you, this line that I took out due to rusted connection nut to the end of the brake hose, was in perfect condition along the rest of the line. I had to use dremel grinder to scrape it off. This is after 18 years of salty road exposure. The weakest point seems to the nuts and not the steel line.

The weak link is the paint on the line. Once It fails at any point it will spread. In your case the nut likely cut through the paint during installation allowing the nut to weld to the line.

When using machines to fabricate, steel lines have the advantage of rigidity they stay perfect from fabrication to installation so there are definitely benefits.

Nicop Is 10x easier for DIY so the advantages vaporize quickly.