John Deere 6.8L OEM Diesel Operator's Manual
![John Deere 6.8L OEM Diesel Engine manual cover](/images/tNbRbpxrGqoRbRVDWmqGndtz/thumbs/thumb175x175.webp)
Regular maintenance intervals include changing the oil and filter every 250 hours, inspecting the air filter every 500 hours, and replacing the fuel filter every 500 hours or annually.
Check the battery connections for corrosion, ensure the fuel system is primed, inspect the starter motor, and verify that the engine has adequate fuel supply and air flow.
It is recommended to use SAE 15W-40 engine oil that meets API CI-4 or higher specifications for optimal performance.
Regularly maintaining your engine, ensuring tire pressure is correct, using the engine at optimal RPM, and avoiding unnecessary idling can improve fuel efficiency.
Common signs include rough running, misfiring, increased fuel consumption, and excessive smoke from the exhaust.
To reset the service light, turn the ignition key to the "on" position without starting the engine and hold the reset button on the dashboard until the service light blinks and turns off.
Stop the engine immediately, allow it to cool, check coolant levels, inspect the radiator for blockages, and ensure the fan is functioning properly.
Ensure all engine mounts are secure, check for misfiring cylinders, balance the rotating components, and inspect the driveshaft for alignment issues.
Turn off the engine and allow it to cool. Remove the air filter cover, take out the old filter, clean the housing, and insert a new filter. Ensure the cover is securely fastened.
Black smoke is often caused by incomplete combustion. Check for dirty air filters, clogged fuel injectors, or an over-fueling condition. Also, inspect the turbocharger for proper operation.