Did rhe tundra upgrade a couple of months ago with no problems. Within the last week this has happened 3 times. When I go to brake, the pedal is rock hard and I have to push real hard to stop. Brake fluid is full. What else can I check to try and figure this out?? Thanks in advance.

 

did you blead the brakes two to three times?

 

Yes we went through a whole bottle when bleeding them. And that was a couple months ago.

 

did you check over all your hard lines to make sure none of them were crimped. and did you buy all new parts not remans or used?

 

We installed new lines with SS 1.2 and the lines appear fine. Any other thoughts???

 

Is it a vacuum booster? Is the vacuum line hooked up/not cracked anywhere?

 

Vacuum line doesnt look bad but am going to replace to b sure

 

is hard from the start of pushing the pedal like you just pumped it thirty times or is it soft for the first quarter of down travel then the rest is very firm because thats the way mine is and it is alot firmer then any other brake pedal ive used.

 

No the pedal is like rock hard and will eventually will go down and the brakes will start to work.

 

huh thats odd

 

Here's an idea to try and locate the problem. Remember to keep your reservoir topped up the whole time so you don't get air in the system

Pull all 4 brake lines out of the calipers and put them into yoghurt containers to catch the fluid. Press the brakes. There should be almost no resistance. If there is, the problem is likely in the master cylinder.

Hook up all but one and press the brakes. Do this for all 4 corners. If it's soft for 3 corners but some resistance when one of the lines isn't connected, it might be a problem in the line to that caliper. Check for a crushed or possibly plugged hard line
If it's soft for all 4, the problem could be in a caliper or booster.

I'm too tired to keep thinking right now, but it sounds to me like either something is binding or plugged in your master cylinder or one/more of your hard lines are crushed somewhere and letting very little fluid through

 

PROBLEM CONTINUES...........Saturday one of the rear wheel cylinders let go and soaked the rear pads. Wheel cylinder replaced and pads. I also replaced the vacuum line to the master cylinder. My problem is that THE BRAKE PEDAL IS ROCK HARD. It doesn't look like I can replace the check valve and might have to replace the brake booster???? I really don't have the $600 bucks for that. ANY OTHER THOUGHT WOULD BE GREATLY APPRECIATED. Thanks.........

 

Guess I will check a yard about 40 miles from here for a used booster.

 

PM sent FJ