I've had a soft brake pedal for several months now, have been intermittently working on it. Brake pedal has 5-6 inches travel before brakes engage, then an overall softness and slow braking.

There are not and never have been any leaks [EDIT: There have been small leaks. This statement was intended to indicate no drops in brake fluid levels and no gross leaks.] Every time I have the hood up (which at least once a week) I check the fluids. The reservoir never drops.

In the last few months, I found both the wheel cylinders to have slight leaks and replaced them. Bleed the brakes afterward. I've also had to replace some drum hardware and adjust the read brakes.

Today I replaced the master cylinder with a rebuild. Bench bled it, then bled all 4 wheels. Some air came out of the fronts, but all 4 ran clear once I was done. Pedal is still very soft.

The pedal is very firm with truck off or battery on, but sinks to the floor when I start it. Pumping doesn't help. Rechecked for leaks, none present.

Any ideas?

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99 3.0 4x2 XLT - Ext cab - Automatic

Sounds like air in the hydraulics, possibly the rear shoes weren't adjusted correctly (or self adjusters aren't working), and since it's a 99 there *could* be a chance that a hose is going bad/bulge under pressure (aged rubber).

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Red flag is raised, these two very conflicting statements in the OP make me wonder about a few things, things like, the details, service techniques, etc..........

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2004 Ranger FX4 Level II, 5R55E, Sonic Blue Pearl

Proudly JAP/RICE free since March 2000

Sorry, that didn't really say what I wanted it to. What I meant was that the fluid level has never noticeably dropped, and I haven't found any gross leaks. The leaks at the wheel cylinders were both minor, and I only found them by gently pushing back the rubber bushings.

I'll amend my original post.

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99 3.0 4x2 XLT - Ext cab - Automatic

Have been going through this with the wife's 2002 Taurus with 4 wheel disc brakes. Put on a new master cylinder (bench bled), replaced the front rubber brake lines (they bulged a tiny bit), and bled the brakes a total of 4 times. Like yours, pedal is stiff before car is started which supposedly eliminates brake booster being faulty. The brakes work O.K., but pedal is soft and not to my liking--especially when compared to my truck. Finally took it to Ford dealership--they checked everything out and said all was O.K., but I had them bleed the ABS system (supposedly Ford has a special machine to do this and most repair joints don't). Helped a little, but not much. So we're living with it. Have also heard you can cycle/bleed the ABS system by running down a gravel road and hit the brakes hard and cycle the ABS system to firm up the pedal. Tried that and it didn't work either.

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2006 Ford Ranger XLT, 2-Door extended cab, 3.0l, Automatic, Air-cond., Cruise, AM-FM Stereo (no CD), ARE Impulse camper shell, Plastic Bedliner, and that's it, as far as extras.

2 possibilities, 1. your rear brakes are way out of adjustment(most likely the issue) or 2. your caliper pins are seized and the caliper isn't sliding as it should.

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2010 Ranger XL 2.3L 5 Spd 3.73:1 Bone Stock
2013 Scion FR-S 2.0L/H-4, 6spd, 4.11:1 Fast Enough Stock