I'm working on reviving a 2004 Ranger XL rwd. When I picked it up, only the rear left brake was working. I replaced front calipers, pads, rotors, and all the rear hardware and wheel cylinders. I bled the master cylinder and all 4 corners until clear fluid came out(master cylinder never ran dry). Now it is braking from both rears but the fronts don't engage unless i press much harder. The first 1/4 of the brake pedal is soft but they will slow. With the front in the air and car off, i can stop the front wheels from spinning with no problem.

Does this sound like a master cylinder or booster issue? The fronts don't seem to engage unless i brake very hard and the rotors still have the cross hatch pattern.

 

You probably have 4 wheel ABS, 4WABS

Does the ABS light work?
Does it light up when key is turned on?

The Master should have two brake lines coming out, inside it is a proportioning valve, this sends 70% of braking pressure to front wheels and 30% to rear wheels
(cars use 60/40 proportioning valve, pickups 70/30)

So yes could be Master is the problem, not booster

In 2001 Ford also added Electronic brakeforce distribution, which "aids" proportioning using ABS module.
If ABS light works and does not come on while braking then Master would be what I would change next

 

The ABS light does turn on when keyed on but not while braking. I noticed the master only has 1 bleeder facing the passenger side in the center of the master. Is there another bleeder? I just remembered i have new front brake hoses. I will try replacing them then go to the master cylinder. Thanks

 

One thing I noticed while driving a few blocks in the rain today was the abs would kick in when coming to a stop. The ABS did not activate when braking normally until the last foot or so when stopping. Would failing ABS sensors cause the braking issue I'm having?

 

May be but unlikely.

Turn front wheels all the way to the Right
Look behind drivers side wheel for the Brake line
And now look for an electrical line, wires, connected to a Front Wheel ABS sensor

If there are no wires then you don't have 4WABS so no way ABS could effect it
If you do it is only a maybe

 

I definitely have abs sensors up front.

 

In case anyone else does a search and finds this. It turns out my abs sensors were dirty causing it to kick in at low speeds and my master cylinder needed to be replaced. It was leaking fluid past the first seal but seemed to recover it on release and not leak into the booster.

 

Thanks for the update

Never heard of dirty ABS sensors and not feeling the ABS pulsing if that were the case, odd one indeed

Yes, Master has two sections that share a common reservoir, one for front brakes and one for rear brakes.
If seals should leak on one section you won't loose both front and rear braking
Or if a brake line should break or leak you would still have some braking from front or rear

 

I've had the dirty wheel speed sensor thing on my Cobra before. It would cause poor or intermittent reading of the tone ring.
Just glad it was a cheap and easy fix overall.