Ok yes another thread, only b/c they still aint right..and its driving me crazy!
96 T100 x-cab V6 4x4..

I had the calipers and hoses replaced about a year ago, went wheeling and since then the brakes aint felt right. I used to be able to stop on a dime..now it sucks!

Bled them no less than 10x, using 2 man method, 1 man and a bleeder kit and a power bleeder at my shop. Everytime after that they felt better but got worse about a week later. Only thing I may have screwed up was I kinda ran the master close to dry b/c I forgot to add fluid one time, but since then its been bled 5-6x..

Had the truck in for some suspension work and the drivers caliper locked up..replaced both calipers with loaded ones from bendix and bled about 3 weeks ago.

Now when I go to stop it doesnt stop well and jolt you out of the seat like it should-it more or less gradually decreases and then finally stops. Pedal isnt that easy to push-it isnt hard but it sure isnt mushy either. Before this whole problem I could jam on the brakes, they would grab well and the ABS would kick in and pulsate..I also couldnt spin the tires with the brakes on period b/c they held so well. I can now spin with the pedal to the floor.. Also when I hit them hard and then get back on the gas it doesnt release properly-it locks them up and when I hit the gas it lurches and i can feel it releasing hem..

Another observation is when you hit the brakes pulling into a parking space they should grab well..it doesnt do that.. The calipers are BRAND NEW-they did rust however but just the outside ..

The only thing that isnt new is the rear wheel cylinders, the master cylinder, booster and hard lines. Rear are properly adjusted, fronts seem adjusted fine as well, pins are clean, etc..

I just dont get it, why on earth wont it stop properly? Is it b/c of the cheap pads on the rebuilts..i would assume it wouldnt stop as well but now it barely does like I said above. There is plenty of fluid and its bled, there is no brake fluid anywhere at all leaking I can see, the calipers are working properly..etc..

I have never had to do this but the FSM shows that you can bleed the brake master by opening the pipe connections as it doesn't have a bleeder screw. I can't see how to do this without making a mess and then you'll have to bleed the whole thing over again and you'll replace almost all the brake fluid bleeding after this. Give the calipers a couple whacks with a wrench with the bleeder screw open and maybe you'll see a small trapped air bubble come out.

Try stopping on a gravel road in 2wd. See which wheels lock up. Could give a clue.

Does the pedal sink if you hold pressure on it? If so then your master needs a rebuild. It only takes a couple minutes to rebuild it.

It could be that the calipers are binding. They can resist clamping as well as releasing. They should have a grease like plastilube or caliper grease in these places:

Pad retaining pins
Contact surfaces between pad/caliper
Pistons where they contact the pad

For what it's worth, after I put my front end back together, the brakes worked like crap. I hadn't bled the LSPV. That helped a lot.. I suspect you know about this and have bled it, though.

I wish I had an adapter to use my power bleeder on the truck. It works a lot better than mityvac.

Well im going to my shop today and my buddy is gonna give it a shot..

First thimg im doing is gonna bleed the system totally, then take it from there..

i had some cheap CSK Auto brand pads in for a year, i couldn't stop to save my life with those, braking hard wouldnt even lock up the tires, bled them and it made a little difference, new rotors, fresh brake fluid, Hawk pads and it stops great, the rears however are crap, need to put my proportioning lift bracket back on there...

Well now that I took off the rear drums I looked at them and the shoes are no good and the wheel cylinders arent much better. The truck does 200k on it and I doubt they were ever changed.

They are also FULL of mud from wheeling..the drums, the shoes, the whole thing..

You can rebuild the wheel cylinders in 5 minutes, there is a $20ish kit at the dealer for both cylinders. If you need pistons there is a separate kit with rubber + pistons for one cylinder. If you push them out far enough to check them you'll get air in and have to bleed again!!

There's a gasket between the hub and drum too, it costs a few cents.

At least you didn't find a brake drum full of oil

Well I am gonna see if we can just get new ones tbh and go from there as the new ones are only about 20..

Dealer is open today so we may windup there instead if the only parts store aint got them..Either way they look trashed and full of mud.

Again, my problem is: I jam on the brakes the truck stops almost like I am gradually pressing the brakes, ABS doesnt kick in and when I go to hit the gas again the brakes kinda stucka nd finally unlock.. I dunno..but the mud in the rears aint good period..

End result..

The cylinders weren't releasing properly. Went to napa and bought a set of shoes and wheel cylinders for 65 bucks..

Replaced both shoes and wheel cylinders and adjusted everything properly, cleaned the mud off too. Then re-adjusted and bled after I drove it a for a bit..

Pedal is good, I can stop but I am plagued by the low pedal syndrome since its lower than I would like. meh..

This whole thing is starting to piss me off..

Here's my recent brake issue.

ABS works fine until I turn the steering all the way right or left (i.e. getting into a parking spot). When I brake at a few MPH, the pedal does that wierd ABS float thing and I hear a loud drone noise from the front brake. This is on pavement with perfect traction. I took out the ABS circuit breaker and the problem went away. I'm not sure if I can trust the ABS in my 97 T-100 anymore.

Any suggestions?

Read the DI chapter of the FSM.

http://users.757.org/~ken/T/04-Diagnostics.pdf