Ongoing shortages of replacement parts for failed diesel exhaust fluid quality sensors are believed to be causing thousands of trucks nationwide to be disabled and parked.
The sensors, which measure the quality and level of diesel exhaust fluid in the tank, are part of the global computer chip shortage, causing a backlog and rising the price of available parts from around $300 to as much as $7,000. Failure of the DEF sensor can result in the vehicle being inoperable. More than a million engines, representing more than 40 engine families (since 2016) could be affected.