Medium and Heavy Trucks
Have Truck Repair Questions? Ask an Expert
Hi my name is***** will be glad to try to help. Please post the complete engine model number and the serial number from the engine tag so I know what engine you have. I log in periodically throughout the day for follow ups and we can post back and forth as needed
Black smoke is overfueling so first check the air filter for restrictions and the turbo for damage and that it spins freely without drag in the bearings engine off/intake boot removed and spinning by hand.
It can also be fuel related or hydraulic if something is holding the engine under a load. Let me know the engine info and I will give you more detailed information for your engine model