1993 toyota landcruiser brake problem

Sounds like vacuum brake booster diaphram has failed. its behind master cylinder and probably needs replacing.

Sounds like your brake booster could be bad. It is the round fat disc shaped part behind the brake master cylinder against the firewall in front of the driver's seat in the engine compartment.

It wasn't clear from your listed problem, but if the car also pulls to one side or the other while you are braking, then the problem could be a seized front brake caliper.

Hey wally wheres the beav????
test it!!!! ok booster... pump your pedal with the motor off and 3 times hold the pedal down Now start the car does it drop in a few seconds..no its booster problems the check valve on the vacuum line should be changed with the booster ..you should have at least 14 in hg Vacuum from the engine .

Nspect brake pads if disc front, inside and outside pads both sides and rear lining condition both sides. Worn out pads and shoes heat up fast causing brake fade and become increasingly inefficeint as you approach a stop and apply more pressure.

• before pulling wheels, do this isolation tes.
• At about 5 miles per hour or less in a safe paved area, let go of stering wheel and brake hard.
• to locate the more efficeint side. It will pull/steer in that direction then pay attention to the brake componants of the oposite side..
• to test the reasr, at samt speed, let go of steering wheel and apply the parking brake gradually bring car to a stoppay attention to which way the vwhcle tens to go. the efficeint side will try to stop and the bad side wants to keep going, causing steer to side that is trying to stop.
• Sticking or binding disc calipers or pistons will cause premature lining wear and brake overheating. The pressure hydraulicly appled will overcome a any piston (disc) resistence when being force out of it's bore. With the mileage indicated, A complete brake job is advise. If these are all drum brakes the wheel cylibers probably won't hold a cup seal for very long. I would bet they are already leaking. I recommend turning "resufacing" rotors if equiped and turning rear drums. Wheel cylyders aren't worth honining so if needed, just repace them. To complete and ensure a thorough job. Have the master cylynder remove and check for cup leakage where it bolts up to vacuum assidt. Replace if needed and have tech flush all old brake fluid through the sytem when bleeding. I believe in replacing all return springs and hardware and have caliper if equiped serviced replace o rings and libricating slides and guides. Sounds like alot, but most rear end collisions could be avoided with just one more foot of rfficiency. Sorry this was so long. Good luck, give yourself a brake from worry. Tire pressures also affect brake longivity and eficiency. Happy trails,Co 7196