Brake Master Cylinder 2004 Discovery SE
 

Our mechanic supplied two sheets of various repairs on our 2004 LR Discovery SE....quoted a new brake master cylinder $577...I'm assuming that includes labor. He noted that it was leaking and needed replaced. (I verified it is leaking)

Reviewed a video and will attempt a replacement myself. Any words of wisdom where to purchase the part and if I need more than just the master cylinder?


Thank you for any information...

you can purchase a good aftermarket one from numerous vendors but the issues is do you have a odb2 tool that will do a power bleed or access to a buddy that has one? When you mess with the abs block or master cylinder you need to do a power bleed to get the trapped air out of the system. Lucky8 has the master cylinder, Atlantic British, eBay, amazon, etc. anywhere from $120 on up. If you go time to wait, get the part number and order from over seas and u can get it still cheaper.

The mechanic did a brake fluid flush/bleed on Jan 11, 2017. So after we replace the master cylinder do I need to do another bleed once it's installed?

Yep. This one is a software based one to get the air out of the abs unit and the master cylinder.

Thank you for your words of wisdom. I am ordering from Lucky8 right now. I am a land rover lover chic and wow...love my LR but am tired of all the repairs

Where are you located at? I'm sure there is somebody in your neck of the woods that could help by having the diagnostic tool to do the power bleed. I'm actually waiting on mine Hawkeye total to come from England

I'm in Idaho. I think my brother-in-law might have one. He's pretty mechanically inclined. Is the diagnostic tool LR specific?

it has to be somewhat lr specific. The process is called a power bleed. You can do the traditional bleed and get a lot of your pedal back and if all else fails, take it to a independent rover shop or dealership and they can do one for you. Probally about the same fee as the diagnostic charge

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you rock! Thank you so much for enlightening me on this stuff. I truly appreciate it.

No problem man. We are all here to help each other and offer any advice we can, albeit sometimes we get it wrong but usually somebody will chirp in and help out also. I know some people have tried to do it then using bill decent and bleeding 3-4 times by the rave manual and they say that works but I have always done it by the book, especially on something as critical as brakes. I would reccomend getting a good scanner like a Hawkeye or lynx if you plan on keeping it for a while. If you do, check with the U.K. Vendors. They are astronomically cheaper. My Hawkeye total was only $300 and it covers every Land Rover up to 2015 and the lynx is windows based and only unlocked for 1 vehicle model. Both are made by britpart and are the folks that designed testbook and t4. The Hawkeye is handheld kinda like a snap on for a big shop and the lynx just hooks up to a windows laptop or tablet.

If a mechanic says your master cylinder is bad I will assume he knows what he is doing and recommend you proceed as you are doing. However, be advised that leaking fluid is common in our rovers and usually is the rubber grommets leaking between the master cylinder and the brake fluid reservoir. A master cylinder repair kit will have them included for about $75?, as I recall. Or you can order the grommets only from a company in Australia for about $16 plus expensive shipping and lengthy transit time. Again, this is for leaking brake fluid directly below the reservoir. If you are having brake pedal fade then repair or replace entire master cylinder to be safe.

What he said...
 

Most of the time it is the master cylinder reservoir which is leaking. If you're careful when you remove the reservoir and replace the seals you don't have to bleed the system as you just top up the fluid so no air gets into the master cylinder.

No telling how many people have replaced the MC itself due to the leaky reservoir seals. I found a retailer out of Australia that sells the 2 grommets. Are you aware of a US supplier?

OP: If the MC leaks but the brakes continue to properly function then you need only replace the seals, not the MC itself.