BRAKES STILL NOT RIGHT

[jugglerone]

Master cylinder, brake hoses a d now an an a pump swapped out and still the vehicle drifts and creeps forward intermittently when at a light or stop sign unless I really push hard on pedal. When driving along and I push the brake pedal the truck stops as it should but if say your on the brake and your just slowing it just seems to give up and when you push pedal it is harder and also does not stop want to stop the vehicle. Thus is all intermittently. No rhyme or reason.

Also the brake booster was checked and it had vacuum in it.

 

[shucker1]

Did you bench bleed the mater cylinder before installing?

 

[jugglerone]

And now an ABS PUMP

Yes the master was bench bled.

 

[jugglerone]

So when you apply the brakes and your slowing down it eventually just seems like it gives up the pressure and when you push more on the pedal it just isn't the stoppage power.

 

[Rick]

Also the brake booster was checked and it had vacuum in it.

Almost seems like a vacuum leak. Have you tried to see how long it will hold vacuum for?

 

[jugglerone]

I remember the mechanic that checked it took the vacuum hose off while vehicle sat overnight and you could hear air when it was taken off.
It's really weird problem as I have owned a 91, and 2, 92 Explorers. But I believe they may have had a different ABS setup.

The vehicle will drift once stopped very easily if you don't really keep pedal down.

 

[Rick]

They went from rear wheel only ABS to 4 wheel ABS in '94 I think.

Have you checked for leaky calipers, rear brake cylinders, fittings etc?

 

[jugglerone]

Yes they are all good. All Replaced when I bought it 2 years ago.

 

[Rick]

I know it was bench tested, but I am still thinking the problem is related to the brake booster or a vacuum issue. I would check all your vacuum hoses to ensure nothing is rotted and that nothing has come off. Also check that your PCV valve is working properly. Perhaps it's stuck open.

 

[BKennedy]

I know this sounds goofy, but give it a try. With the engine not running. Pull the fuse for your brake lights. Get a piece of wood or whatever will fit and wedge it against the front driver seat so the brake pedal is depressed about half way to the floor, or until it hits firm resistance. Crack open your master cylinder fill cap (leave the cap on, just crack it open). Leave overnight. With steady pressure on the pedal, it will force any air in your brake system up through the master.

I had a bunch of issues with soft pedal feel when I did my solid axle swap. I replaced everything and it did not help. I gravity bled, power bled, you name it, I tried it. Turned out most of my issue was too much pressure going to the rear brakes so I installed a adjustable proportioning valve. That, and superduperbitchen slotted and drilled rotors and superduperbitchen ceramic pads.

But, the above procedure really helped with firming up the pedal, maybe it will work for your issue.

Rick is correct that the first generation Explorers all had rear only ABS, except for the 1994's.

 

[jugglerone]

My 1993 has 4 wheel ABS.

 

[Rick]

My 1993 has 4 wheel ABS.

My '93 had rear wheel only. Mix and match? LOL

 

[Rhett]

I had a bunch of issues with soft pedal feel when I did my solid axle swap. I replaced everything and it did not help. I gravity bled, power bled, you name it, I tried it. Turned out most of my issue was too much pressure going to the rear brakes so I installed a adjustable proportioning valve. .

Did you keep your 4WABS when you did your SAS?

And this thread motivated me to tackle my own soft pedal issue. I may end up replacing the master, because after bleeding twice I still can't get pedal -- I may have crudded up the diaphragm in that old master. Anyway, look what you made me do jugglerone.

 

[Rick]

Did you keep your 4WABS when you did your SAS?

And this thread motivated me to tackle my own soft pedal issue. I may end up replacing the master, because after bleeding twice I still can't get pedal -- I may have crudded up the diaphragm in that old master. Anyway, look what you made me do jugglerone.

Did you do a rear disc conversion?

 

[BKennedy]

I am not a fan of ABS on a off-road type vehicle. I want to be in control of my brakes. I swapped in disc brakes out of a 1999 Explorer. Replaced the master cylinder with a 1999 unit, no cruise.

 

[Rhett]

Did you do a rear disc conversion?

No, I still have drums. I'm going to bleed all four wheels one more time. If that doesn't work I'll test the brake booster, see if it's doing its job. That will then leave the master cylinder as the culprit... or so the plan goes.

 

[Halford1]

I had this problem once. I lost control of the brakes and made several turns to slow down my 99 Explorer. The trusted mechanic I had found that several parts in the Brake Master cylinder was in need of change, and it solved all the brake problems.

 

[Rhett]

Did you do a rear disc conversion?

I got productive this evening like I sometimes do...tested the brake booster -- ok. That left the master. So I changed it. One side (I guess the rear) on the master was not putting out fluid at all (well, just a trickle) -- so it was worn out. Bench bled it, installed it, bled all four wheels. Now has *good* flow coming out the rear bleeders. Has good pedal sitting in the garage. Tomorrow, test drive.

 

[jugglerone]

Update.....After all of the parts, labor and aggravation a garage came to the conclusuon to change the master cylinder again and I reluctantly went to get a replacement at Advance Auto which is where I bought the first replacement 2 years ago.....AND THAT FIXED IT!
So the replacement was faulty as the original.
The good news is that the brakes now work as they should.

 

[Halford1]

Congrats on the brake fix!