2017 Toyota 4runner Brakes Problems

Your brake master cylinder failed, which controls your braking system. This is unusual for a newer vehicle with low mileage, and the mechanic indicated it shouldn't typically happen this early. The repair will likely involve replacing the brake master cylinder and possibly bleeding the brake system to restore proper braking function.

While driving on the freeway, your brake pedal became soft and sank nearly to the floor when you needed to brake suddenly. Your ABS (antilock brake system) didn't engage as expected, and you barely managed to stop without hitting another vehicle. Since then, you've noticed the brake pedal feels soft until you pump it several times. A dealer diagnosed a failed ABS actuator assembly that needs replacement at a cost of about $3,800 including labor.

While turning into a parking lot, your brake pedal suddenly went all the way to the floor with no braking effect. After releasing and reapplying the pedal, you were able to stop. Your brake fluid level is normal with no visible leaks, but the problem recurs and dealerships can't reproduce it. This issue has been reported by other 4Runner owners on forums, and suspicion points to the antilock brake system (ABS) electrical components.

When you apply the brakes hard at speeds of 35 mph or higher, one wheel on the left side locks up, causing your vehicle to swerve violently and become difficult to control. The owner tested this repeatedly on a grassy field and confirmed that one left-side wheel skids while braking hard, though the problem sometimes improves after multiple brake applications in succession. Two Toyota dealers told the owner the brakes are working as designed, but the owner believes this is dangerously unsafe. The fix may require inspection and potential replacement of the anti-lock braking system (ABS) components or wheel brake cylinders on the affected side.

VEHICLE BOUGHT NEW 8/2017. HAS APPROX. 7,000MLES. THIS IS THE 3RD OR 4TH SIMILAR INCIDENT BUT THE MOST SEVERE. DRIVING ON I-95, APPROX. 60 MPR, TODAY, WHEN I APPLIED THE BRAKES THEY SEEMED TO LOCK AND ALTHOUGH MY FIRST THOUGHT WAS THAT THE CAR ALSO ACCELERATED IT MAY HAVE BEEN ONLY MY EXPECTATION OF SLOWING DOWN AND THAT WASN'T HAPPENING. THE BRAKE PEDAL ONLY SEEMED TO COMPRESS ABOUT 2-3". LUCKILY I WAS ABLE TO PULL OVER AND THE CAR DID STOP. I CONTINUED ON WITHOUT INCIDENT BUT LIKE I SAID THIS WAS THE 3RD OR 4TH TIME AND THE MOST SEVERE.

APPROACHING AN INTERSECTION ON CITY STREETS I EXPERIENCED TEMPORARY BRAKE FAILURE. WHEN APPLYING THE BRAKES TO SLOW DOWN THE PEDAL WENT ALL THE WAY TO THE FLOOR AND DID NOT SLOW DOWN THE VEHICLE. AFTER ROLLING THROUGH THE INTERSECTION WITHOUT INCIDENT I PUMPED THE BRAKE PEDAL A FEW TIMES WHICH RETURNED THE BRAKES TO AN OPERATIONAL STATUS. THIS HAS HAPPENED 3 TIMES IN 2 DAYS. OTHER TOYOTA 4RUNNER OWNERS HAVE ALSO REPORTED THE SAME OR SIMILAR ISSUES IN THE LAST 12MONTHS.

I PULLED UP TO A STOP LIGHT AND APPLIED THE BRAKES. I STOPPED BUT WHILE I WAS SITTING WITH THE BRAKES APPLIED, MY 4RUNNER STARTED ROLLING FORWARD. I HAD TO PUSH THE BRAKE PEDDLE TO THE FLOOR TO A POINT I COULD BARELY REACH TO GET IT TO STOP AGAIN. I TOOK IT TO THE DEALERSHIP AND THEY AGREED THE BRAKES WERE NOT ACTING RIGHT. THEY COULD SEE ON THE COMPUTER THAT SOMETHING WAS WRONG AS WELL. THEY SAID I WOULD NEED A NEW MASTER CYLINDER ON THE 4RUNNER. THE VEHICLE IS ONLY 2 1/2 MONTHS OLD WITH 2500 MILES. WHEN I PICKED UP THE VEHICLE, THEY SAID THEY TALKED WITH TOYOTA AND IT WAS ONLY THE 2ND CASE OF THIS HAPPENING IN THE US. THE MORNING IT HAPPENED IT WAS AROUND 30 TO 35 F OUTSIDE. WHEN THE DEALERSHIP TESTED IT THEY SAID THEY APPLIED THE BRAKES TO STOP AND IT SLOWLY STARTED MOVING FORWARD AFTER A FEW SECONDS LIKE HAD HAPPENED AT THE STOP LIGHT. THEY REPLACED THE MASTER CYLINDER AND WHEN I PICKED IT UP EVERYTHING SEEMED TO BE WORKING OK.

RE: COMPLAINT 11043597. EXPERIENCED COMPLETE LOSS OF BRAKES. NO WARNING LIGHT. BRAKES WERE RESET? AFTER VEHICLE ARRIVED AT DEALER. ECU DID NOT DOWNLOAD ANY WARNING CODES. BASED ON THIS, TOYOTA WILL NOT REPAIR/REPLACE CORRESPONDING BRAKE COMPONENTS AND WANT ME TO DRIVE THE CAR. THIS WAS A COMPLETE BRAKE LOSS WITH PEDAL TO THE FLOOR AND NO BRAKES. USED PARKING BRAKE AND TRANSMISSION TO STOP CAR. CHECKING THE NET, THERE ARE OTHER 5TH GENERATION 4RUNNERS WITH SIMILAR BRAKE FAILURES AND SIMILAR NO ACTION FROM TOYOTA

BRAKE FAILURE. APPROACHING 4 WAY STOP. WENT TO APPLY BRAKES, HEARD-FELT A POP AND PEDAL WENT TO FLOOR AND LOST ALL BRAKING POWER. THIS IS A NEW VEHICLE. HAD TO USE PARKING BRAKE AND TRANSMISSION TO SLOW TO STOP. FORTUNATELY ONLY GOING 30MPH........STILL ROLLED INTO CENTER OF 4 WAY INTERSECTION. THANK GOD NO CARS IN FRONT OF ME OR THERE WOULD HAVE BEEN AN ACCIDENT.