DIY: 2006 BMW E53 X5 3.0i Brake Line Replacement

[Clavurion]

M12x1,0 mm nipple on front left side connection only. (The point where those lines could be mixed.) Others should be M10x1,0 mm. If those old nipples are not badly corroded you can reuse them but of course preferably renew them too.

https://www.realoem.com/bmw/enUS/sho...diagId=34_0980

[andrewwynn]

I just looked at my photo album and I marked the pipes red and blue for port and starboard. Port is the odd size.

Starboard pipe:

https://www.fcpeuro.com/BMW-parts/X5...ds=34326755666

Port pipe:

https://www.fcpeuro.com/products/bmw...mm-34326752219

Prices came way down on the port pipe. I'd have bought oem prefab. They don't come bent you still have to bend them.

[BenFenner]

Originally Posted by Clavurion

M12x1,0 mm nipple on front left side connection only. (The point where those lines could be mixed.) Others should be M10x1,0 mm. If those old nipples are not badly corroded you can reuse them but of course preferably renew them too.

https://www.realoem.com/bmw/enUS/sho...diagId=34_0980

You know, I've had that page up and looked at it many times, even clicked on the M12 hardware to see where it was in the diagram. But I'm so busy/frazzled these days it didn't register in the proper section of my brain. Thank you for hitting me over the head with it. So just one of those M12 deals, and only in that one spot. Perfect.

Originally Posted by andrewwynn

I just looked at my photo album and I marked the pipes red and blue for port and starboard. Port is the odd size.

Cool, cool.

Originally Posted by andrewwynn

Prices came way down on the port pipe. I'd have bought oem prefab. They don't come bent you still have to bend them.

Yah, the OEM lines are priced decently right now, but learning the new OEM lines are not pre-bent was really the tipping point for me. If I'm going to have to bend my own lines, I might as well bend them with material that is much easier to bend and is more corrosion resistant than factory steel to boot. Yah I'll have to flare my own lines and source hardware, but in the end I think I'll be much happier with this solution.
(I expect to have to replace a handful of plastic tube retaining clips as well.)

Cheers everyone, I'll report back how it went but won't have the full update ready to post to my build thread likely for years. I'm so far behind posting updates.

[andrewwynn]

Very true on bending nicop vs. steel!

[BenFenner]

I'm reporting back to cry and offer advice.

I just spent 5 hours removing the rear brake lines from the ABS pump back to the caliper flex lines. Boy, what an obnoxious job. I've done some horrible jobs before, and this is right up there. At least I realized quickly I was going to have to remove wheel well liners and such. I'm quite sick and skipped lunch so I'm sure that didn't help. =P

So everything is pretty straightforward except that joint for the rear-right wheel where it takes a 90-degree turn to go across the width of the car above the rear sub-frame. That one as has been mentioned is a total bitch, but if you're like me and removing absolutely every piece of hardline for the rears, you can remove it from the caliper flex line at the rear-right wheel and fish it across the car* enough to bring that junction within easy reach of normal flare wrench tools. So no crows foot necessary for removal. Installation might be another story. We'll see.

Cheap, foam ear plugs are nearly perfect to block up the exposed ports while you wait for parts to arrive.

One other piece of info. Again, if you're like me and removing everything from the ABS pump back, you'll find the rear-left line has a M12x1.0 thread into the ABS pump, as well as one more down by the front-driver's rocker panel. So not just one junction with M12, but two for a total of three M12 male hardware and one double-female M12 joiner.

At least I know what hardware I'd like to purchase now, and that 25' of tubing won't be nearly enough (I need about 34 feet if I make no mistakes). And now I know all about those one-time use plastic pop rivets for the fender liners (another tool to buy!). Wish me luck on the install. These lines that go over the wheel arches look insane to reproduce. We'll see.



*You might have to half-remove the right-rear damper (just the bottom bolt) to allow for the hardline to get into position. I had to. And that's an obnoxious job as well if you don't realize there's a non-captured nut on the other end. That's not how my E36/8 nor E91 are. Live and learn. At least I didn't totally ruin things like I thought I had when the bolt just never backed out and kept spinning with aluminum chips falling out.

[Bmwe5320023.0]

- The bolt that comes with the metal line: factory is M10 x 1.0.
Make sure you get the bubble flare type with M10 x 1.0 bolts.
Do NOT buy the bubble flare line with "Standard SAE bolts".

- Note that for two (2) REAR brake lines, BMW used different unions
M12 vs M10 to prevent confusion in the factory assembly line. But
both pipes are the same with O.D. = 4.75 mm.


Anyone got a link for these? I'm a bit confused what exactly is needed and what's the length of these bolts?

[Bmwe5320023.0]

For anyone visual like myself, here's what's needed

[Bmwe5320023.0]

2 x 25 feet was the perfect length to redo all lines.
I found the job super easy except for the front passenger side line.
It goes behind the engine, and I still haven't figured out how to remove it. Maybe will cut it in the middle and the just use a coupler. I don't see how to remove it from the top if removing the full line. On the left side of the engine, the A/C line that's connected to the evaporator core would have to come undone. So maybe somehow it clears from the bottom?
Anyone replaced the full line on front passenger side, from ABS to the caliper hose?

[BenFenner]

I only did the rear lines from the ABS unit all the way to the caliper. My front lines were in good shape. I would imagine those lines are installed before the engine/transmission, so no surprise you're having trouble. Just add another coupler like you've suggested. I imagine it's the way to go.