jackieonassis

Lately I have been driving and the brake peddle becomes super hard as if i have been pumping it and the brakes lock up. I don't come to a screeching halt, it just makes the car rumble in the front and hard to drive. If i stop at a light and start again, it feels like i am smashing on the brake every time i shift. I am certain that there is something funny happening.

the weird things are:

1. if i park the truck when the brakes are locked for about 1-2 hours. the brakes return to normal. i dont do anything but let it sit.
2. while i am driving. i don't have to ever hit the brake peddle and the brakes will lock up. i mean. i can not once touch the brake peddle and it will lock up. ??

i did just replace my carburetor before this started happening. not that it is related, but that is the only thing that i have done.

i just took my truck to a shop today. they said the pads are fine, but the fluid was orange and rusty. they flushed the fluid out of the entire system. i drove it fine for about 30 miles and then the brakes locked up again. ???

83yota6996

bleed all your lines and see if any of them are plugged up.

jackieonassis

i think that is what they did at the brake shop today. they had a machine hooked up to all four wheels and where sucking the fluid out and replacing it with new fluid. is that bleeding?

rock slayer

if there was a petrolium product put in there before then the rubber in your system would be deteriorated and could swell and the pressure exerted would apply your brakes(this happened to me when i got the bottles without labels mixed up and put power steering fluiod in my master cylender..... i had to replace my master cylender and rubber lines to fix it)

jackieonassis

o you are suggesting a new master cylinder and brake lines?

83yota6996

u might also have a sticky master cylinder, rust or something of that sort in the master cylinder piston.

rock slayer

maybe next time it happens loosen the brake line where it connects to the master cylender then tighten it back up (this should relive pressure to release your brakes) if this works your brake lines probably are not blocked
my buddy did the same thing that i did (power steering fluid) and just replaced his master cylender and that worked for him(didn't need to replace lines)
i replaced everything because i had it on hand... you might just need a new master cylender its wayy easyer than replacing brake lines

83yota6996

Toyota brake systems SUCK!

rock slayer

i think they work great unless you put power steering fluid in them lol (hey it looks the same!!!!)

jackieonassis

hahahahaha. thanks! hahahahaha

jackieonassis

ok. ordering the master cylinder now.

4Crawler

iTrader: (3)

Might also check your brake booster. It uses engine vacuum to make the brakes work easier and something there may have been messed up when you swapped the carb. since you indicated that was a recent repair before the brake problem occurred.

Scooby098

Mine was doing the same thing I went through 4 MC's bad parts store. you could bits of rubber seal in the MC fuild. if it dont fix it go to a differnt parts place or upgrade to the v6 mc.

yzrider273

yea mine are doing the same thing on my 86 4unner!!! it sucks it started happening a couple months ago i rebuilt the calipers and bled the system, and the master cylinder is about 2 years old... and they still lock up while driving
could it be the proportioning valve???
or the booster???

jackieonassis

the master cylinder was the problem in mine. it looked kind of new, but i got a replacement anyhow. as soon as i switched it out i was golden. well. i switched it out, bled the cylinder but opening the screw on the side of it and pumping the brakes. then i bled the brakes, all of them. and then i was all set

yzrider273

nice!!
well come to find out it was my brake booster that was cause of my troubles
there was a gnarly leak right were the rod comes out