How much damage does putting unleaded gasoline in a diesel engine cause?

Catastrophic damage can result from putting unleaded gasoline in a diesel engine, including piston, wrist pins and connecting rods destruction. Unleaded gasoline can also reduce the necessary lubrication of sensitive components and eventually destroy them.

The amount of diesel fuel remaining in the tank at the time unleaded fuel is added and the age of the engine determine how much damage a vehicle may incur. Any amount of unleaded gasoline in 2007 or newer vehicles is likely to damage emissions control components and systems; whereas in older engines, reduced engine power, more noise and warnings from the emissions sensors are likely side effects.