There are various things that can affect a loss of Fuel Mileage on a Semi truck, some of them we will list below. With Fuel prices being ridiculously high these days it’s important to isolate the problem and get it fixed as soon as possible.
- DEF Sensor: After Treatment: This is one of the most frequent. If your outlet or inlet sensors are not working properly they can send incorrect signals to the 7th injecter (Diesel Doser).
- Diesel Doser: There has also been claims of Dosers getting stuck open, causing excess fuel to be distributed to the aftertreatment system.
- Tires: incorrect inflation
- The Clutch Fan: If the clutch fan stays on it can significantly cause unnecessary stress on your engine and thus increase the amount of fuel consumed by your truck.
- Dirty injectors.
Why would a clutch fan stay on?
Often times it can be as simple as a clutch fan solenoid not working properly.