Rusted brake lines in GM pickups demonstrate the twilight zone of auto safety

This week's hearings into the botched recall of 2.6 million cars by General Motors produced more heat for the automaker and regulators than light, with GM chief executive Mary Barra excorciated by lawmakers for the automaker's mistakes. All of the questions built from the same unstated premise: cars and their parts should always be safe, and automakers like GM should fix them when they’re not.

Yet in many cases, how the industry and government regulators define a safety defect isn’t a yes-or-no question — and it’s another GM issue involving millions of vehicles that demonstrates the twilight zone in between.

For more a decade, thousands of owners of GM full-size pickups and SUVs — mainly the Chevy Silverado and GMC Sierra — have complained to federal regulators and GM about rusted brake lines. The trucks use small steel pipes to route brake fluid between the wheels and control pumps, and those lines can rust to failure, especially in northern states that salt their roads frequently in winter.

It’s a well-known problem among GM truck owners and mechanics, several of whom have documented their troubles in online videos. While most of the complaints involve models made between 1999 and 2006, some newer vehicles have seen complaints as well.


And scores of owners have reported a sudden brake failure while driving due to their rusted brake lines giving way on the road. One owner told federal officials about just such a failure in a 2005 Silverado this February:

While approaching a red light at 28 mph and pressing the brake, the pedal went completely to the floor and the vehicle did not slow down. I pumped the pedal repeatedly and only slight braking action could be achieved. I went through the intersection just narrowly missing two crossing cars and turned onto a nearby side street. After finally getting the vehicle to stop, I got out and saw a puddle of brake fluid forming a few feet behind the driver side front wheel.

In March 2010, the National Highway Traffic Safety Administration launched an investigation into the problem, counting 763 complaints including 26 crashes and three injuries. NHTSA also found that the failure rate of brake lines on GM’s trucks in winter states was far higher than in warm-weather states — 43 per 100,000 sold in the north vs. 3 per 100,000 elsewhere, and that in a quarter of cases the system failed on the road without warning. In January 2011, NHTSA upgraded the probe to an “engineering analysis” on at least 1.7 million vehicles, often the final step before an automaker issues a recall or the agency orders one.

Since then, there’s been silence.

The NHTSA analysis has now been open three years without a resolution — the oldest open case at the agency today, and the second-longest probe in its history. Most investigations are resolved either with a recall or a finding by NHTSA that no action was necessary in a matter of months, but the GM case has lingered as the agency has collected data from automakers and updates with GM.

NHTSA declined to comment, citing a policy of not speaking on open investigations. But in previous cases, similar delays were a sign of the agency simply not being sure whether to press for a recall, typically in the face of an automaker’s opposition. Its longest probe, a question about roll-aways in older Ford Explorer SUVs, went 3 1/2 years before NHTSA decided to close the case without taking action.

GM maintains brake lines failing due to rust don’t pose a safety problem, saying even if one should fail suddenly, the system has separate circuts that should still bring the truck to a halt, and that dashboard warning lights and brake fluid leaks are enough to warn owners before an emergency. It also contends other automakers have brake lines which rust and fail, and that such parts should be checked just as brake pads and discs are.

In response to continuing complaints, GM does offer a discounted brake-line repair kit, which it estimates should cost about $500 versus the $2,000 such a repair had cost in the past.

As with the Cobalt recall, GM's bankruptcy shields it from liability for any crash that happened before July 2009. And as NHTSA interim chief David Friedman told Congress this week, the agency has no set rules for opening, closing or pushing for a recall — leaving truck owners who worry about the safety of their vehicles to watch, and wait.

"We look for further evidence, we look for trends, but we consciously do not have a threshold," Friedman said, "because each case is different."