I need to replace the rear brake line on my 2004. Buick LeSabre. How long do I make the brake line?

First, you need to inspect all the metal lines under your vehicle to make sure that the rest does not show ANY sign of rust and if you find any sign of rust, then they will need to be replaced as well. Most of the lines run parallel with the frame of the vehicle, jack the vehicle up and support it with jack stands so you can safely work on it!

You will need a few tools, line bender, tubing cutter, flaring tool, correct sizes of line wrenches, string, tape and some type of stiff wire such as a few metal clothes hangers straightened out. You can use some string to find out the length, tape 1 end of the string at the first junction/union in the line needing repair/replacing. Run the string along the line, you can tape it where ever needed to hold it to the line, until you get to the next junction/union.

Once you have traced all the bad area of your line(s) that needs to be replaced then cut/mark your string and remove it from the bad line & measure. Now, with me saying this, you ALWAYS will need more in length on the new/replacement line as some of the bends you can not duplicate exactly! For instance, if you figure you need 36" inches of line, (unless the line has NO BENDS in it), I would safely figure at least another extra 12" inches! Every bend has a take-up of length in it, which means the line will be shorter after you make said bends!

Next, using the straightened out clothes hanger wire (or any other stiff but bendable wire), use it as a guide to use when you go to make the same bends in your replacement-new line. You can hand bend the bends & angles and such in the wire so you can use it as a pattern to duplicate them in the new line. Make sure you use flared fitting unions to join each section of metal line together!

NEVER use compression type fittings on brake lines!!! If your not sure of how to do this procedure correctly, I would HIGHLY suggest taking your vehicle to a qualified repair shop. We are talking about your brakes, if you can not stop properly, not only are you putting your own life in your hands (and whomever else may be riding in your vehicle), but other motorists on the road with you as well! And, this shouldn't cost all that much to get it repaired. Always price around! Get at least 2 estimates or more, most shops may give free estimates. :)

And, if you can do this repair, ALWAYS check for leaks after repairs have been performed! You will have to bleed your braking system to get all the air out of it and this is not easily done if your vehicle is equipped with ABS. Once all air has been bled off and you have good brake pedal again, have someone crank vehicle and apply a lot of pressure to the brake pedal while at the same time you inspect each junction/union for leaks! Also, make sure that the new line is supported & routed away from any/all moving parts as well as hot exhaust. Hope this helps you.

Just have to roughly measure it first before getting new line and add 10% for good measure, use a piece of string and trace along the brake line with it , much easier than a ruler