Skip the auto shop - Our mechanics make house calls

Q: Rusted brake line - 1999 Mercury Sable

asked by on

I'd like to replace the brake steel pipes/unions (or brake lines, I've heard them called either one) myself. My mechanic has informed me after inspection that they are rusted through, and I've noticed the red brake sign flicker on the HUD near the odometer from time to time (very infrequently). I just went to Autozone to replace them but they need to know the size of the diameter. I have no jack or way to lift the car up so that I can measure them myself, but I figure that is easy info a Mercury Mechanic would know.

My car has 104000 miles.
My car has an automatic transmission.

Hey there. 3/16 inch diameter brake line tubing is used on virtually all cars and trucks made in the world. The more important issue is what type of end fittings you have and type of flare (bubble, inverted, etc.). That can be discovered on disassembly or with reference to the Factory Service Manual.

It is highly recommended that steel tubing NOT be used to replace defective brake lines. New steel tubing will corrode just like the old. However, if you replace the brake (and fuel, too) lines using DOT approved Ni-Copp tubing (or comparable), the lines will NEVER corrode again. Plus, Ni-Copp in 3/16 inch sizes is practically bendable by hand. Ni-Copp is incredibly easy to work with and the ductility of the material creates a perfect seal with minimal torque.

Ni-Copp is probably vended with pre-made ends to fit your application but if you desire to create your own flare ends FedHill sells an excellent flaring tool kit to make professional flares in Ni-Copp or steel tubing.

If you would like a certified professional to assist you with parts procurement, planning, and execution of your brake line repair, by all means contact YourMechanic.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Ask a Mechanic
(100% Free)

Have a car question? Get free advice from our top-rated mechanics.

Ask A Mechanic
Over 10,000 questions answered!

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: Trunk broken

The door latches are a common failure. Each door will need to be separately diagnosed, since they may have different broken pieces. I recommend that you have a mechanic, such as one from YourMechanic, inspect your door latches, and have...

Q: heater not hot.

Hi there. Assuming, the temperature blend door is properly functioning, would lead me to believe the heater core is restricted or air is trapped and a cooling system flush could resolve the issue. The heater control valve and/or vacuum control...

Q: when i brake on my 2008 550i bmw it sounds like a grinding noise in the rear around the middle. Do you know what it could be?.

Grinding, squealing, or other "noise" on braking is usually related to a brake pad/rotor contact problem. These surfaces "mate" when you apply the brakes and if there is scoring on the rotor, rust, dirt, irregular wear on pad or rotor,...

Related articles

Rules of the Road For Iowa Drivers
Driving on the roads requires knowledge of the rules, many of which are based on common sense and courtesy. However, even though you know the rules in...
What are the Car Pool Rules in Hawaii?
Hawaii is widely regarded as a land of vacation and relaxation, and as such, its scenic roads and routes are far better known than the state’s freeways. But, as with all...
How Much Does a Mechanic Make in Vermont?
Automotive technician jobs in Vermont have an average mechanic salary of $37k, with some mechanics earning a salary of $53k.