Having a bit of a brake issue on my '87 that I'm not sure on. It is a 1987 D100, 2WD, slant 6, auto. It sits a lot, I drive it about 500-1000 miles a year. The pedal has recently gotten extremely soft. If you are fast on the brakes, it is very firm and stops on a dime as it always has, but if you are gentle on the pedal like rolling up to a stop sign, the pedal will slowly go all the way to the floor and you will have next to no stopping power at all. The last time couple times I've had soft bake pedal issues with this truck it was because the spring in the right rear adjuster is weak and sometimes when you set the parking brake and let the truck sit for a month or so it will lose the adjustment in that corner. But this time it only has a soft pedal if you brake slowly. What I can compare the pedal feel to is when you have a bad wheel cylinder on an older Chevy how the pedal will slowly travel to the floor as it pushes the fluid out the leak. Anyhow, I have checked for leaks and do not have any (and the reservoir is still full) so I was leaning towards a failing master cylinder perhaps? Anyhow, I'm a Chevy guy for the most part and know ALL the common failures on them, but not so familiar with the common problems on a Dodge. Don't take that the wrong way though, I've had this Dodge forever and love it to death, just hoping to get a little insight and sorry about being so wordy. Thanks a million :-)

 

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