CVSA warns against manually adjusting auto slack adjusters

Truck News

TORONTO, Ont. — A surprise brake blitz by the Commercial Vehicle Safety Alliance (CVSA) in May has led inspectors to believe there’s a big problem with drivers manually adjusting self-adjusting slack adjusters.

“A significant problem we are noticing in recent years is the practice of manually adjusting self-adjusting brake adjusters,” said Stephen Campbell, executive director of CVSA. “If you have a brake that is over-stroking and it has a self-adjusting (automatic) brake adjuster, you more than likely have a problem with the brake or the adjuster. If you readjust it, you aren’t fixing the underlying problem.”

There are concerns that truckers may have a false sense of security after manually adjusting automatic brake adjusters, which will likely fall back out of adjustment before long.

The Canada and US-wide 12-hour brake blitz was part of the CVSA’s Operation Air Brake campaign. More than 11,900 vehicles were inspected during the May 7 unannounced blitz.

“Poorly adjusted or defective air brakes reduce the braking capacity of large vehicles and further increase their stopping distance, said CVSA’s Campbell. “Even under ideal conditions, the stopping distance of commercial vehicles can be twice as far as that of cars and other smaller vehicles. Having defective brakes increases the risk to the driver and any passenger, as well as to others traveling the roads”.

As part of the blitz, 93,751 brakes were inspected. Nearly 10% of vehicles were placed out-of-service for brake adjustment defects; 8.3% were put OOS for brake component defects; 15.8% were placed OOS for brake-related defects; 9.4% of brakes with manual brake adjusters were placed out-of-service; 3.8% of brakes with self-adjusting brake adjusters were deemed unfit; and 4.7% of all brakes inspected were placed OOS for brake adjustment defects.

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  • How much cash did the transport departments make on this “blitz”? Its all about making money. Safety is a secondary issue