When Jimmy is off brakes are firm when I start Jimmy brakes are soft why and how do I fix this?
Does the vehicle actually have a braking issue or does the pedal just bother you. When the truck is off you do not have assistance from the vacume boster to help brake. The pedal will be softer when the truck is on. If you notice that the pedal is softer than it used to be when on it could be air in the lines, bad caliper if its disc brakes,or bad wheel cylinder if drums. Could be other standard brake issues as well.
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