An attentive driver’s 911 call this week led state officials to stop a tow truck using an unsafe combination of a metal pipe and chains to tow a big rig, officials said.The caller reported seeing a big rig towing another tractor-trailer on a San Francisco freeway using nothing more than the pipe and chain, a method the CHP described in a Facebook post as unsafe and illegal. Typically, operations like that require specialized tow trucks, officials said. CHP officers from the Golden Gate Division quickly intercepted the vehicles and upon inspection, they found additional safety hazards, including the truck’s brake chambers dragging along the roadway — a clear sign of faulty brakes.
Officers cited the driver at the scene and both vehicles were towed away. CHP officials credited the alert motorist with helping avert a potential disaster…