Everytime I pull out from a stand still I have a horrendous squeal. It's only noticeable moving forward, nothing if in reverse. While driving down the road it makes a grinding sound for a while (10-15 min). If parked on a slight slope the truck won't move - heck our driveway has a little grade and it barely rolls down. Yesterday, I parked on a flat surface and the truck came to a stop almost by itself. My brake pedal barely moves when the brakes applied. It moves maybe 1/2-1 in., but will lock the brakes if moving slowly. Moving down the highway the brakes are harder to slow the truck. I know I got boost going to the booster because when I start the truck, the pedal will move down if I am pressing it.
Also, the e-brake doesn't work. That is probably my fault, I took the rear wheels off to see if the rear drums were locking up. The left rear one was so I backed down the adjuster. Now the e-brake doesn't work at all.

Man, I need some help with this.

thanks

 

Sounds like a problem with the brake shoe hold-down springs broken or loose. Jack up and turn one wheel at a time to determine which one. Remove drum to inspect/repair.

 

If the flex lines are dry-rotted, they may also have collapsed inside. Check them for visible cracks on the exterior, they may not be leaking yet, but soon could, and leave you with no brakes at all.

If they have collapsed, they won't allow the brakes to return to the "idle" position.

 

Sounds like you have a serious problem with your brakes engaged all the time. All your symptoms describe it.
Squeal from stand still - or groaning. Inertia wants brake pads to keep grab of the rotor yet the engine is more powerful so it moves.
It only makes noise moving forward because of the design of brakes having more grip moving forward. Anybrakes will allow you to reverse easier than forward.
Driving down the road warms up the pads until the heat buildup creates brake fade to some degree.
Parking on a grade and not able to move means your brakes are applied.
Same with stopping by itself on a level.
Moving down the highway the brakes are harder to slow the truck because of brake fade from the heat buildup.
Having brake boost does not help your situation. Your brakes are already applied.
Your e-brakes not working is a different thing. Get new cables where the old ones bind. Usually the whole cable right to the drums are rusted, specially all the cable housing assemblies.
All your troubles will be gone if you get your brakes serviced. Do not cheat on brakes. It's not worth it. Do not machine used rotors. Rotors are heat sinks that absorb the heat buildup from braking. The thinner the rotors, the weaker the heat sink which will create worp and then you have pulsating brakes.
If you want, get the cheapest new rotors rather than the premium quality brand. This is because the cheap ones will last half the lifetime of the good ones but probably only 1/4 of the price.

Good luck.

 

Would this be ALL brakes applied or just 1? I did notice today that they were all free until I applied them, then the left-rear locked up - tell tale skid mark. Sometimes they're free, sometimes not. When they are free, they'll 'clunk' when I hit the pedal. I am trying to narrow it down to cylinders and calipers - or the differntial valve. I just need a way of troubleshooting. I was thinking of disconnecting each component 1 at a time and pushing the pedal down into a bleeder bottle. I figured if they all push fluid out (and don't suck air) then the differntial valve is ok. Then I'd just replace the calipers and the cylinders. Any suggestions?

 

In general, when brakes are applied, all brakes should exert the same amount of pressure on the pads, the front being stronger because they are disc pads. However, all things considered, in normal braking, you should not nose dive unless you jam on the brakes.

When you have less traction because of condition of the ground, or when you have faulty brakes, many things can happen and hard to diagnose.

The simpler and safer way is to check all components for proper function.

Consult a pro. Take your truck to a shop and ask for a brake system check. Most shops will perform a quick check and advise you what is needed. They want to have your business so they will tell you what they think you need. By doing this you have a good starting point. Now you can confirm their check. If you think you are able to do the job, you are that much further ahead.

Going down the check list:

1) Master cylinder working?

2) Vacuum boost working? Any vacuum leak?

3) Brake fluid clean? Flush and bleed with fresh fluid to get rid of dirt or air.

4) Brake lines good? Any leaks at junctions? Any rusted lines?
5) Front calipers working freely? Calipers should slide on the mounts and caliper cylinders should not bind when retracted inward with a twist. Lube the slides with brake lube.

Tip: caliper travel in time will wear a rut on the shoulder where it slides. The amount of travel is the amount of movement it takes to apply the brakes. When you change to new pads, the travel is at a different position. However the rut will not allow the caliper to move beyond the valley of the rut, thereby maintains a squeeze on the brake pads, causing brakes to be applied all the time.
Find the rut and use a grinder to smooth it out without changing the angle of the shoulder and make sure you don't remove too much metal.

6) Front rotors should not be scored. A little is ok. Replace instead of machining if bad. Machineing will eventually create warped rotors and will give pulsating feeling when braking. (too much heat buildup and thin rotors will warps them)
7) Rear cylinders should not be rusted. Good idea to replace old rusty ones. Make sure cylinders can be retracted by the brakeshoe springs.
8) Make proper adjustment on the tightness of the rear shoes. The drum should slide on the shoes with a very slight resistance.
9) Use brake clean spray to degrease the surfaces of brake pads and rotors and drums. Don't make any more finger grease on them. Be clean when you work.
10) Finally check action of the brake pedal when you drive. It should not feel spongy (air in lines), or take too much effort to stop (pads not gripping or they are dirty or not adjusted on the rear clearance).

By all means the above is only what came to my head right now. It is not the manual.

Hope this helps.

 

I would go ahead and replace both rear wheel cylinders, since they are cheap, and it's an easy thing to do. I would concentrate on the rear first since you said one of them locked up.

Don't panic if you twist one of the brake lines off the rear wheel cylinder. They get rusted and stuck. Just buy a piece of that universal brake line and run it from the t-block to the wheel cylinder. The universal ones are usually a little bit too long, but you can make some extra curves in it and it will work out.