[Waldo]

Uh, what kind of malfunction exactly? The issue discussed in this thread is still 100% safe to drive, just a little noisy

[wasiloff]

Waldo, on 26 August 2010 - 11:59 AM, said:

Uh, what kind of malfunction exactly? The issue discussed in this thread is still 100% safe to drive, just a little noisy

-In general, the vehicle feels unsafe to drive due to severe braking system deficiencies.

-Under moderate braking from around 30 or 40 MPH, an audible grinding noise is generated along with harsh vibration conditions.

-Vehicle braking capability appears to have degraded to an unsafe and unpredictable performance level

All 3 dealer corrective actions have actually worsened the condition.

[Waldo]

wasiloff, on 26 August 2010 - 02:46 PM, said:

-In general, the vehicle feels unsafe to drive due to severe braking system deficiencies.

-Under moderate braking from around 30 or 40 MPH, an audible grinding noise is generated along with harsh vibration conditions.

-Vehicle braking capability appears to have degraded to an unsafe and unpredictable performance level

All 3 dealer corrective actions have actually worsened the condition.

That doesn't tell me anything. Audible grinding noise and vibration is not unsafe. Calling braking "unsafe" without giving any detail doesn't help. High or low speeds, hot or cold temperatures, pedal feel or actual response, ABS activation or not?

There was a new TSB published just last week. Have your dealer try that out.

[wasiloff]

Waldo, on 26 August 2010 - 03:38 PM, said:

That doesn't tell me anything. Audible grinding noise and vibration is not unsafe. Calling braking "unsafe" without giving any detail doesn't help. High or low speeds, hot or cold temperatures, pedal feel or actual response, ABS activation or not?

There was a new TSB published just last week. Have your dealer try that out.

Please let me reiterate the conditions associated with this failure mode:...

-Speed at which failure mode consistently occurs: when braking from 30-40mph
-road condition = nominal, dry, level, paved highway
-Braking demand = moderate
-Pads appear to be wearing extremely prematurely (under mostly light duty highway driving cycle conditions)
-ABS not active when phenomenon occurs
-No change with different environmental profile oberved, Temperature / humidity do not appear to be a factor.
-Specific degree of braking degradation in deceleration = unkown (no instrumentation to provide validated data acquisition. Limited to qualitative driver evaluation and perception)
-3 previous corrective actions performed by dealer were not effective in resolving this failure mode.
-Dealer is not ready to execute new TSP. Parts not available.

[Waldo]

I'm trying to help, but you're still not telling me what the problem is. Are you saying that sometimes under moderate braking you press the pedal and the car decelerates at a certain rate, and other times when you press the pedal the exact same amount the car decelerates at a very different rate. Or are you trying to say that while pressing the pedal at a constant pressure, the car changes it's rate of deceleration dramatically during the same stop? At the times when the car isn't decelerating as much as you would expect, does pushing the pedal harder stop the car faster? Does the brake pedal feel change while the braking performance changes? Are you able to engage the ABS in a hard stop?

There are many things that can go wrong in a brake system, from friction surface issues, to leaking fluid lines, to sticking calipers, to booster/vacuum problems and all have different symptoms.