having a serial number off the truck dataplate would insure this is correct but based on a general fault code table here is what i found:
E0428 = Water in Fuel Indicator Sensor Circuit - Voltage Above Normal or Shorted to High Source
E2448 = Coolant Level - Data Valid But Below Normal Operating Range - Least Severe Level

So check your fuel system, filter, drain any water out of it, run engine and see if the code clears up.
Also check your coolant level, sounds like its low