Brakes don’t work properly. Hard to push

I have some troubles with the brakes in my jeep. When I'm driving down hill, it takes a lot of force to actually start braking. The brakes are very hard to press. I found that the wheel cylinders had leaks. I had them replaced and bled on all wheels. Also, I had the shoes glazed. After the repairs, the brakes are still not working properly. The truck doesn't have a brake booster. So, what should I do?
Experienced mechanics share their insights in answering this question :
Since you do not have power brakes, a clogged hose line or fitting may be the cause or a sticking/binding caliper may be the issue. You may want to enlist the help of a mechanic, such as one from YourMechanic, who will have the expertise to diagnose the brake system and perform recommended repairs.

How to Identify and Fix Common car Problems ?

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The most common causes of your brakes not releasing is a seized caliper or brake pad. This typically occurs due to rusting or ageing.
Air in the brake line(s) is the most common cause of a soft/spongy brake pedal. If air gets into the brake lines, it can prevent brake fluid from flowing properly, causing the brake pedal to feel spongy or soft. If the brakes are soft or spongy, this is a good time to change or flush the brake fluid.
If you have a stiff brake pedal and the vehicle has a vacuum pump or hydraulic brake booster, some common issues could be a missing serpentine belt, a failing electric pump, or low power steering fluid.
If your booster doesn`t work, then it can`t deal with the resistant pressure in your brakes. It won`t be able to boost the force you make when you depress the pedal to control your brakes. So, when this happens, you`ll notice a difference in the way your pedal responds when you step down on it.
If your brake booster is leaking but your brake fluid level is full, your brake booster would be leaking vacuum. This would mean that your booster has a crack, the check valve is bad, or the hose that connects to the booster has a crack or hole in it.
Pull the brake lever to check the tightness of your brakes

If the lever touches the handlebars, the brake cable is too loose. If you can barely squeeze it at all, the cable is too tight. Ideally, the brake lever should squeeze 1 to 1.5 inches before becoming difficult.

One common reason is a buildup of air in the brake lines, which usually means your vehicle`s brake fluid needs to be flushed. A lack of brake fluid due to a leak (often caused by rust) can also result in an unresponsive brake pedal.
Try to Pump the Pedal

Your first reaction to encountering spongy brakes should be to rapidly pump the brake pedal with your foot. Even if there is a defect in your braking system, this can usually generate enough pressure to stop safely on the side of the road.

If no vacuum is present or the valve does not open, the brake pedal will be difficult to push. A one-way vacuum check valve from the engine to the booster pulls atmospheric air from the vehicle into the booster. If the check valve leaks, it may allow oil residue to flow to the diaphragm and cause it to fail eventually.
To fix a brake booster leak, you need to replace the vacuum hose, which makes the connection between your car`s master cylinder and the brakes themselves. You can perform the maintenance yourself but it helps to have prior mechanical experience.
Cause: Chronic master cylinder failure due to fluid leaking past secondary seal in the master cylinder bore. A defective master cylinder pushrod seal in the power brake booster allows vacuum to draw fluid past secondary seal of the master cylinder. Solution: Replace both master cylinder and power brake unit.
When a brake leak is present, it affects the fluid pressure in your system. Since it is that pressure that actually causes your wheels to slow or stop when you activate the brake pedal inside your vehicle, your brakes will fail to engage once the fluid levels are too low.
It is most likely that the brake cables and brake housings have rusted. This creates a lot of friction inside them, making it hard to affect the brake arms by pressing the levers, or reverse. If this is the case, you should replace the cables and housings with new ones.
A leaking brake booster may also cause an engine to run badly. Leaks in the brake booster provide a vacuum leak to the engine. One quick test for leakage, is to turn the engine off and press the brake pedal. If the pedal still has one or two assisted applications before getting hard to press, likely no leak exists.
A vacuum hose (also known as the vacuum line or brake hose) links the power brake booster to the engine. It assists in drawing air into the engine to create a vacuum. The vacuum hose may rot or crack at its connecting points, which leads to a vacuum leak. The vacuum leak, in turn, can cause a hard brake pedal.
Brake Boosters that are dented, severely rusted, disassembled, or, are broken in anyway, cannot be rebuilt. In addition, your old unit provided will be sent back to you at your expense.
The brake booster pressure sensor measures the relative pressure in the vacuum booster. In operation, the transducer senses the difference between the applied pressure and the atmospheric pressure via strain-sensitive piezo-resistors which are implanted in the silicon MEMS die membrane.
The most common cause of failure is a leak in the brake lines. The brake fluid will slowly drain out, until there isn`t enough left to transmit the pressure from the pedal to the tires. The brakes can also fail when the discs or drums wear out, so they can no longer put enough friction on the wheels to stop them.
MC: Any brake booster in the world requires 18-inches of vacuum to operate at peak efficiency. Therefore, the pump turns on when it reaches a vacuum level of 18-inches, and it shuts off as soon as it gets to 23-inches of vacuum.
Press hard on the footbrake several times to centralise the brake shoes inside the drum. Raise the car at the nearest jacking point and support it on an axle stand. Lubricate the adjuster with light oil. To move the shoes closer to the drum, turn the adjuster clockwise , as viewed from behind the backplate.
Pressure Differential Switch

The valve/switch kicks in and blocks off pressure to that line, reserving pressure to either the front or rear brakes, allowing you to maintain one or the other so that you can safely come to a stop.

The most common causes of your brakes not releasing is a seized caliper or brake pad. This typically occurs due to rusting or ageing.
By adding force to the master cylinders, which dispenses the pressurized fluid that triggers the brakes, brake boosters lessen the effort required to apply the brakes. Aside from the damage to your car, it is extremely dangerous for you and others on the road to drive with a faulty brake booster.
The brake booster vacuum pump supplies the vacuum required for the power brake booster to work. If it fails or has a problem, the vehicle will be left without assisted braking. Without the brake booster, the brake pedal will be stiff and will require considerably more effort to stop the vehicle.

Relevant Questions and Answers :

the most relevant questions and answers related to your specific issue

Brakes don’t work properly. Hard to push – 1960 Jeep CJ5
ANSWER : Since you do not have power brakes, a clogged hose line or fitting may be the cause or a sticking/binding caliper may be the issue. You may want to enlist the help of a mechanic, such as one from YourMechanic, who will have the expertise to diagnose the brake system and perform recommended repairs.

EPC light on 2004 Jetta. Code said brake switch faulty, but brakes lights worked. Replaced brake switch, now no brake lights.
ANSWER : Hi there. The first thing that pops in my mind beyond of what you have listed is perhaps the electrical harness attached to the brake switch. Perhaps the harness itself is damaged or you have an exposed wire, loose ground wire somewhere. You might want to have a professional mobile mechanic come to your location and complete a brake lights not working inspection to help you diagnose this issue.

I replaced the brake light switch. Gear lever unlocked because it had locked. Now the brakes feel hard.
ANSWER : Hi, thanks for writing in. You need to check the brake switch install adjustment. You may have the switch adjusted too tight and it is holding the the brake pedal partly down. This will cause the brake master cylinder to not release the brakes when you let off the pedal. Readjust the switch away from the pedal until you feel some free play again in the pedal. This should fix the problem. If you would like help, consider having an expert automotive technician from YourMechanic come to your home or office to inspect and diagnose this issue for you, and make or suggest any repairs as needed.

Supportive bar attached to brake pedal interrupts proper braking process
ANSWER : It’s possible to have someone alter the brake pedal or adapt a brake pedal from a different vehicle. You may call around to some customization shops to see if anyone is interested in taking on the project. But first, I would try reaching out to the selling dealer with your concern – especially since it is a new model. Good luck.

When I put my foot on the brake my back left brake light goes off, when I take it off the brake the brake light comes on
ANSWER : I would suggest trying to disconnect and reconnect the wiring to the rear lights. I have seen these older Toyota vehicles rear lighting short out on the lights themselves due to the way the light circuit was made on the lamp housing. Look at the housing circuit on the light to see if one is touching another, and that could tell you why it is malfunctioning. There could also be a problem with the brake light switch. If you are not comfortable dealing with wires, I recommend getting in touch with a certified mechanic who can look at your brake light issue for you to see what’s going on.

Brakes hard to push or stuck in park.
ANSWER : Hi there. Check the parking brake lever and cable. As the vehicle was on a hill and the parking brake was set, the cable could have gotten stuck or the parking brake assembly in the rear brakes could have failed and locked making the lever not return. Check the parking brake lever, cable, and the rear brakes and see if its working. For the service brake pedal being hard to push, there could be an issue with the brake booster with a vacuum leak. Remove and plug up the vacuum line to the brake booster and test drive the vehicle in a safe area. See if the symptoms are the same or get worse. If the symptoms are the same, then I recommend replacing the brake booster. If the symptoms get worse, then either the brake booster has a small vacuum leak and needs replaced or the master cylinder has a broken return spring jamming up inside the master cylinder. If you need further assistance with your brakes not working, then seek out a professional, such as one from Your Mechanic, to help you.

Low brake pedal and anti-lock brakes are not kicking in.
ANSWER : The brake pedal is working to stop the vehicle, but there may be air in the controller unit causing the ABS brakes to not function. I recommend bleeding the brake system from the farthest location from the master cylinder to the master cylinder including the ABS unit. If the brakes are still spongy after a full bleed, then the controller will need to be replaced. If you need further assistance with your brake pedal being spongy, then seek out a professional, such as one from Your Mechanic, to help you.

I got my brake booster replaced that same day I noticed my brake pedal being to high up hard to push up and the shifts no respond
ANSWER : Hi there. Honestly, I’m somewhat confused as to why the brake booster was replaced by the repair shop, when your vehicle was 100% perfect taking it to the shop. The symptoms you have described are that of a failed brake booster. The repair shop should have the opportunity to correct the problem, I would assume at no charge. The lack of acceleration may be the brakes are applied, without stepping on the brake pedal. I recommend having your vehicle’s high, hard brake pedal be diagnosed and repaired by a certified technician, such as one from YourMechanic.