Brake system maintenance

Question

I have a 20-year old Toyota Tercel with 103K miles. It runs well.

Last week, the brakes didn't work. I changed a brake hose because it was leaking and I am going to change the other 3 brake hoses soon, but do I need to change other parts in the brake system to make sure that I will not have a brake problem while driving?

additional details:

The problem showed up Monday morning. The car was parked for 2 days (not moved). The problem was "no brake at all" : the brake pedal sink towards the floor. There was a lot of oil near the front right wheel. The brake light was on, and the master cylinder was empty.

The car is well maintained. I changed the brake fluid twice over the last 10 years. I replaced the shoes early 2016 and checked the rotors and pads. The brake did not make any sound until after the mechanic took out the pads to check the rotors (early 2016). He mounted the pads and told me that I need to replace the pads and rotors after 10k miles.

I always check the fluids in the car. The brake fluid was always light colored/clean.

I have been watching the brake fluid in the master cylinder after replacing the brake hose. It looks good (no changes). The brake pedal is soft. I guess the mechanic didn't bleed the system. when I get the 3 other hoses replaced, I will make sure the system is bled.

The friction parts usually give some signs before they fail. Also I know how long they have been on the car and when I need to replace them, but leaking is a hidden problem that might start/happen at any time even after inspecting the whole system.

Answer 1

Yes, change the hoses. No need to buy 'braided stainless steel' hoses that they might up sell you to in the store; the cheap rubber OEM hoses lasted 20 years.

You might as well change all pads and shoes (and associated hardware), and replace the brake fluid (and then bleed the system). Check the rotors and drums for wear (replace if scored). After all that, you should be good.

Note: Don't drain the brake system at any time, unless you want to take the brake master cylinder out and bench-bleed it. Which you don't want to do!

Answer 2

I would say that every component of the brake system should be evaluated to make certain you will "not have brake problems while driving." Particular attention to friction materials (pads in front, I suspect on a 1996 Tercel shoes in the rear) are the major wear components, but rotor discs and drums should also be evaluated.

As @Pete suggested, brake fluid is often the most negelected [and critical!] part of any modern hydraulic braking system. Not only does this stuff wear out and get dirty, it's also hygroscopic (absorbs moisture) which is a bad thing as the water boils easily at temperatures seen in braking systems.

Pads, shoes, rotors, drums, no leaks, and fresh fluid. I'd feel confident if these things are well in order.

Answer 3

I think there is no reliable answer possible. We do not know enough about the state of your brakes. Can you describe the color of the brake fluid? Did the brake totally failed to break or was there only a weak breaking? Where there any unusual sounds? If the fluid is very dark it would be an indication that maintainance got neglected. The most serious answer would be to suggest to do a complete brake-service:

• Inspect the brakes. Measure the thickness of the rotor and pads/linings, compare to the datasheets. If necessary, replace. Check for leaks, the cylinders in the drums often fail. Check also the brake calipers, inluding the cylinders and the guidance bolts.
• If a cylinder in the drum leaks: replace both cylinders and the brake linings.
• Clean the inside of the drums. Attention: brake dust is dangerous to your health.
• Change the other hoses.
• Replace the brake fluid.
• If the old fluid is very dark: I would suggest to overhaul/replace the master cylinder and the brake balancer.

It may be seem overkill, but a defective brake is nothing to take easily.

Edit: Reuse the car only alter you clearly identified the cause of the fault and fixed it. Otherwise: Tow the car to a professional and let him fix it.

Edit, concerning your addition: If the whole brake is failing then there must be a failure at the master cylinder. Even if a leak happened to the brake hose or an error happened during installation there is still a second, independent brake circuit. The only single point of failure would be the master cylinder, except of course that the two brake circuits got defective at about the same time. I have a strange feeling in my gut (I cannot figure out why one leak can cause two circuits to fail and emptying the master cylinder) but logic tells me that the master cylinder must be defective.

My suggestion: Get it towed to a mechanic. You need to replace the pads/rotors, fix the leak (most possible a brake hose), replace the master cylinder and bleed/fill both circuits (including the abs block).