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Brake System Maintenance

Contributed By: Joe Sego

I won't bother you with another how-to on replacing brake pads or shoes. Want I want to address is the need for brake fluid replacement. IMHO this should be done every two years or so.

This task is seldom done on vehicles, but, it's very important. Yeah I know "my brake system has 220k miles on it and it's fine" well I say you are lucky. The brake system is very prone to absorbing moisture. Moisture is the #1 killer of calipers and lines, not to mention the master cylinder.

Brake fluid absorbs moisture. Ever wonder why your fluid looks different shades of brown? *Water* i.e. moisture has caused rust in your system and contaminated the fluid. Quality brake fluid is clear or slightly off color.

Changing the system of all it's fluid is easier than you might think. Several methods work well. I'll not cover the vacuum pump method which draws in new fluid as the old is removed. My preference is the easiest method but takes a bit of time and you can do it alone! No need to have someone pumping the peddle and all that. let's use gravity to change that fluid!

"What type of fluid should I use?" There are several choices, many swear by the 100% silicone fluids. Silicone brake fluid will not absorb moisture as fast as DOT 3, but many complain of a soft peddle with silicone. I would suggest using what your Owner's Manual suggests. Most likely DOT 3. Very cheap too. Depending on your vehicle I would start out with a couple quarts.

The tools you'll need are few. Here is a sample;

  • Jack stands ( don't cut corners here!)
  • Good floor jack (dittos)
  • Brake fluid
  • Six point socket for bleeders valves
  • Short length of rubber hose to fit bleeder nipples.
  • Container to catch old fluid

Be extra careful with brake fluid as it will remove paint!

The gravity method is the (imho) the simplest and safest method to change your brake fluid. I also use the gravity method to bleed my brake systems.

  1. Jack up the truck and use jack stands.
  2. Remove the wheel(s) not mandatory but easier.
  3. Start at longest brake line and work towards shortest; right rear, left rear, right front, left front, in that order.
  4. Loosen the bleeder valve and attach the rubber hose to it and put other end of hose in a container. The fluid should start to flow.
  5. At the master cylinder add some fluid as necessary to the rear half of reservoir. Do not pump brake peddle. Let fluid flow until it runs clear. (remember to keep adding fluid to master cylinder as needed)
  6. This process takes a bit of time, but, you will end up with an 'airless' brake system, plus you can do this alone.
  7. Do not move to the next wheel until the fluid runs clear at the current wheel. You'll have time to do other maintenance while the brake fluid flows!
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