I call this a "Panic breaking defect" I have experienced this on two different GMC vehicles manufactured 14 years apart. The first was a 1999 GMC suburban with mechanically operated throttle control. The second was my present GMC Yukon XL Denali with electronic throttle control. The defect: The close proximity of the accelerator pedal to the brake pedal makes it possible to have the right foot on both pedals at the same time. This results in high engine RPM and full breaking pressure, however, the anti-lock breaking system releases and re-applies the break pressure repeatedly allowing the vehicle to lunge forward a short distance on each cycle. To remove ones foot from the both pedals so as to apply it to just the break would result in the vehicle, engine being at high RPM, to allow the vehicle to speed forward resulting in a serious collision. True one could use the left foot, if able, on the break and then remove the right foot, allowing the engine to return to idle but on modern automatic transmission equipped cars where the left foot plays essentially no part in driving, such an action is not likely to occur. Also the ignition key could be turned off but with both hands employed to apply maximum pressure on the steering wheel to ensure maximum braking effort, that is not likely to occur either, besides that would result in lack of power steering and vacuum boost to the break system. A proposed solution: In a drive by wire environment it would be simple to send an idle signal to the throttle body every time the break pedal is pressed and this is the condition which occurs in a normal breaking situation. I have related this to the service manager of my local dealer and have also communicated it to General Motors Customer Support even offering to demonstrate the problem but have received no response. After all I am only a lowly customer and it matters not that I am also a retired Engineer!

- Sheboygan Falls, WI, USA

The contact owns a 2013 GMC Yukon. While driving various speeds, the brake warning indicator illuminated. The contact added brake fluid to the vehicle and the indicator illuminated again, but there was no fluid leaking from the vehicle. The contact was an independent mechanic who stated that the brake fluid was leaking into the vacuum canister for the power brake. The contact also mentioned that the failure could not be detected unless the vehicle was diagnosed. The dealer was not contacted. The contact repaired the vehicle himself. The manufacturer was not made aware of the failure. The failure mileage was 134,000.

- Lees Summit, MO, USA